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I'm sure there have been improvements in LiPo and Li-Ion lifetime, but I find the claim of 1000 cycles for LiPo dubious. Got a link for that? Anyways, according to this link http://www.thermoanalytics.com/support/publications/batterytypesdoc.html Li-Ion can have from 400-1200 cycles and LiPo 400-600 cycles. This link http://batteryuniversity.com/learn/article/is_lithium_ion_the_ideal_battery also states that Li-Ion can do more charge cycles than LiPO. Perhaps your experience with poor lifetime was on a hot running laptop? Heat is usually the main culprit when we are talking about ridiculously short life for Li-Ion or LiPo.

The typical chemical battery used in hybrids have very poor efficiency. ...

Source please? Last I've heard, Nickel-based chemistries (early hybrids such as the Prius use(d?) Ni-MH) achieve 90% charging efficiency if fast-charged (that is, the battery stores 90% of the energy provided to it). And Li-ion's charge efficiency reaches an impressive 99.9%.
While compressed air may have many advantages over modern batteries, charging/discharging efficiency is unlikely to be one of them.

The typical chemical battery used in hybrids have very poor efficiency. ...

Source please? Last I've heard, Nickel-based chemistries (early hybrids such as the Prius use(d?) Ni-MH) achieve 90% charging efficiency if fast-charged (that is, the battery stores 90% of the energy provided to it). And Li-ion's charge efficiency reaches an impressive 99.9%.
While compressed air may have many advantages over modern batteries, charging/discharging efficiency is unlikely to be one of them.

Sorry I don't have the science on me... I looked into this a while back. I believe the overcharge and heat both lead to the same basic chemical oxidation. Fully charging (and especially overcharging) is a huge cause of internal heat. And while there doesn't seem to be anything specific thing you can do to save batteries, there are a lot of things you can do to kill batteries.

http://batteryuniversity.com/learn/article/how_to_prolong_lithium_based_batteries

And as to your suggestion, there are battery systems that wait for a little while then do full charge / discharge cycles. They tend not to be on laptops, as people wouldn't want to grab their laptop in the middle of a full discharge.

Things that will kill your battery:

1. Charging it topped off at 100%.
2. Fully bottoming it out at 0%.
3. Not cycling it at all.
4. Heating it too much.
5* Cooling it too much.
* Cooling is actually beneficial in the long term. But in the short term, while it is cold, it will reduce or kill it's output.

Well people claim the batteries don't need conditioning, but that in many cases it takes a few charge/discharge cycles for the software to correctly display the charge level.

That's exactly right. The advice that I've received says to charge li-ion batteries as frequently as possible, but if you want your battery meter to remain honest you'll need to run them down occasionally. It's best to avoid doing this more often than necessary -- deep discharge cycles impose more wear and tear on the battery.

I plug my Droid into my work PC in "charge only" mode and allow it to charge off USB while I'm at my desk. It also charges overnight while I sleep. I rarely let the battery run past 50-60%, so I know I've always got some runtime in reserve when I need it.

Some charger manufacturers claim amazingly short charge times of 30 minutes or less. With well-balanced cells and operating at moderate room temperatures, nickel-cadmium batteries designed for fast charging can indeed be charged in a very short time. This is done by simply dumping in a high charge current during the first 70% of the charge cycle.

In the second phase of the charge cycle, the charge current must be lowered. The efficiency to absorb charge is progressively reduced as the battery moves to a higher state-of-charge. If the charge current remains too high in the later part of the charge cycle, the excess energy turns into heat and high cell pressure. Eventually, venting will occur, releasing oxygen and hydrogen. Not only do the escaping gases deplete the electrolyte, they are highly flammable!

Lithium ion batteries lose capacity for several reasons. First is the age from manufacture. In this case, a two-year old laptop might've gotten a battery that had been sitting in a warehouse for a few years. Second is the temperature. A battery in a desktop replacement laptop that's never below 60 degrees Celsius will degrade at an astounding rate, whereas a battery sitting in a plastic bag in the refrigerator will hardly degrade at all. Third is the number of charge cycles (rather straight forward). Fourth is how long the battery spent completely discharged. Modern batteries will shut down before before being completely depleted, but if this fails or if you don't immediately recharge them then some cells might die. Fifth is how long a battery was kept at high charge levels. A battery kept at 100% charge won't last nearly as long as one kept at 80%, 60% or 40%.

So, the best situation for a lithium battery is sitting in a plastic bag in a refrigerator at 40% charge, where it'll lose ~2% capacity per year. The worst case is being kept at 0% charge in hot temperatures which can make it useless in no time, and the next worse is 100% at hot temperatures (e.g. a laptop on a desk), which can lose a staggering 87% of its capacity in a year. (Yes, that's three hours down to twenty minutes.)

I expect this issue to turn out being that installing Windows 7 reset the manufacturer selected power scheme and probably disabled any charging control software. My own laptop had the "critical" battery level decreased, and the "only charge to 80%" software needed an update from the manufacturer (though in my case it still kinda worked, it just would nag with "Only use Sony batteries" and try to hibernate).

Most of this is from memory, but here's the source for the rest of it.

Lithium Ion batteries do lose their maximum charge over time, that's a fact of physics. How much charge they lose depends on temperature and how much they're charged up.

http://www.batteryuniversity.com/parttwo-34.htm

This isn't as simple as you're thinking. Nickel Metal Hydride batteries are manufactured as a paste and rolled or turned into prismatic cells. It's difficult to recover the elements put into the pack.

Replying directly to your request for a citation, the EPA has a nice page here describing all of the wonderful sickness you can enjoy when you have nickel in your water: http://www.epa.gov/ttn/atw/hlthef/nickel.html

Sounds like a great waste of energy to recover the batteries anyways;

"The recycling process starts by removing the combustible material, such as plastics and insulation, with a gas fired thermal oxidizer. Gases from the thermal oxidizer are sent to the plant's scrubber where they are neutralized to remove pollutants. The process leaves the clean, naked cells, which contain valuable metal content.

The cells are then chopped into small pieces, which are heated until the metal liquefies. Non-metallic substances are burned off; leaving a black slag on top that is removed with a slag arm. The different alloys settle according to their weights and are skimmed off like cream from raw milk.

Cadmium is relatively light and vaporizes at high temperatures. In a process that appears like a pan boiling over, a fan blows the cadmium vapor into a large tube, which is cooled with water mist. This causes the vapors to condense and produces cadmium that is 99.95 percent pure.

Some recyclers do not separate the metals on site but pour the liquid metals directly into what the industry refers to as 'pigs' (65 pounds) or 'hogs' (2000 pounds). The pigs and hogs are then shipped to metal recovery plants. Here, the material is used to produce nickel, chromium and iron re-melt alloy for the manufacturing of stainless steel and other high-end products.

Current battery recycling methods requires a high amount of energy. It takes six to ten times the amount of energy to reclaim metals from recycled batteries than it would through other means. "

http://www.batteryuniversity.com/partone-20.htm

My Motorola krzr k1m (verizon) used to have great battery life, except when running GPS with turn-by-turn navigation (i.e., continuous update of my GPS position). Then a new, fully-charged battery would run down within an hour, and the phone would get noticeably warm. Eventually I started using the navigator function to plan out the next few steps of my trip, then turned it off for a while, then repeated once I got closer to my destination.

Even with such efforts, GPS seemed to kill batteries quickly -- i.e., the battery physically expanded, and its recharge capacity dropped precipitously after a few months. Lithium-ion batteries don't like to run hot, so maybe that was a factor.

I was hoping that the 3G S had avoided these problems, but maybe they haven't...

What exactly is the real-life "catch fire and explode" failure rate on lithium-ion batteries anyhow?

It happens quite often, actually. Anyone who's been flying R/C aircraft for any length of time has either seen it or knows someone that it happened to. A friend of mine damn near burned down his house once.

So stop the evil-corporation conspiracy theory bullshit and do a little research. The Battery University is a good place to start.

This is a real safety issue in which real people are being hurt.

Before posting, I read through the comments here to see if ANYONE had a clue regarding the dangers of Lithium Ion (and especially Lithium Polymer) batteries.

Nope. Not a one. Zero, zip, nada. Everyone wants to bash Panasonic rather than do a little research first.

Talk about knee-jerk responses.

Someone made this point before you, politely and to-the-point (http://hardware.slashdot.org/comments.pl?sid=1280593&cid=28458001). He got a succint answer (and I miss my mod points on both of them), which goes: Have the camera deny to charge the battery, then. Or give, and this is a wild thought, the consumer the choice of whether to use the battery! The really wild thing to do, though, would be this: let people know how the charger operates, so batteries will "fit". Allow only batteries build to specs.

Listen, Lithium Ion technology is DANGEROUS. It catches fire easily -- very easily -- and destroys everything around it.

Credit Sony, who is one of the pioneers (if not THE pioneer) of Lithium battery safety, for protecting their customers.

Sheesh, you people are as bad as any other herd of sheeple. Not everything that a corporation does is evil.

No, but stock-board-shareholder-management mechanisms ensure they will always do what is best for the corp itself, and not give a shit about whether it is evil or not. Assuming they did this for their own sake is not company-bashing; thinking anything else is sheer stupidity and/or an assumption of extreme incompetence on their part. The interesting part is whether they are doing it so their cameras won't blow up and get them sued/blogged about, or to sell more batteries. Me? I think it is a bit of both.

Before posting, I read through the comments here to see if ANYONE had a clue regarding the dangers of Lithium Ion (and especially Lithium Polymer) batteries.

Nope. Not a one. Zero, zip, nada. Everyone wants to bash Panasonic rather than do a little research first.

Talk about knee-jerk responses.

Someone made this point before you, politely and to-the-point (http://hardware.slashdot.org/comments.pl?sid=1280593&cid=28458001). He got a succint answer (and I miss my mod points on both of them), which goes: Have the camera deny to charge the battery, then. Or give, and this is a wild thought, the consumer the choice of whether to use the battery! The really wild thing to do, though, would be this: let people know how the charger operates, so batteries will "fit". Allow only batteries build to specs.

Listen, Lithium Ion technology is DANGEROUS. It catches fire easily -- very easily -- and destroys everything around it.

Credit Sony, who is one of the pioneers (if not THE pioneer) of Lithium battery safety, for protecting their customers.

Sheesh, you people are as bad as any other herd of sheeple. Not everything that a corporation does is evil.

No, but stock-board-shareholder-management mechanisms ensure they will always do what is best for the corp itself, and not give a shit about whether it is evil or not. Assuming they did this for their own sake is not company-bashing; thinking anything else is sheer stupidity and/or an assumption of extreme incompetence on their part. The interesting part is whether they are doing it so their cameras won't blow up and get them sued/blogged about, or to sell more batteries. Me? I think it is a bit of both.

Before posting, I read through the comments here to see if ANYONE had a clue regarding the dangers of Lithium Ion (and especially Lithium Polymer) batteries.

Nope. Not a one. Zero, zip, nada. Everyone wants to bash Panasonic rather than do a little research first.

Talk about knee-jerk responses.

Listen, Lithium Ion technology is DANGEROUS. It catches fire easily -- very easily -- and destroys everything around it.

Credit Sony, who is one of the pioneers (if not THE pioneer) of Lithium battery safety, for protecting their customers.

Sheesh, you people are as bad as any other herd of sheeple. Not everything that a corporation does is evil.

Before posting, I read through the comments here to see if ANYONE had a clue regarding the dangers of Lithium Ion (and especially Lithium Polymer) batteries.

Nope. Not a one. Zero, zip, nada. Everyone wants to bash Panasonic rather than do a little research first.

Talk about knee-jerk responses.

Listen, Lithium Ion technology is DANGEROUS. It catches fire easily -- very easily -- and destroys everything around it.

Credit Sony, who is one of the pioneers (if not THE pioneer) of Lithium battery safety, for protecting their customers.

Sheesh, you people are as bad as any other herd of sheeple. Not everything that a corporation does is evil.

only 500 cycles, really? that seems a little low. do they mean that after 500 charges the battery begins to decrease in capacity, or that the battery will start to fail completely after 500 charges? because that seems really really low to me.

i mean, most rechargeable batteries today are Li-ion batteries, right? i just wanna know how many recharges i have left on my PSP.

does it help if you make sure to plug the battery back into the charger before it's out of charge? what can you do or not do to help preserve the capacity and life-span of a li-ion battery?

Li-ion batteries are usually limited by 'calendar' life, not charge cycles - they start losing capacity the moment they are packaged at the factory and generally last a couple of years before they become too weak to use.

However, there are some strategies to extend their life:

1. Keep them cool (but not frozen)
2. Keep them at around 40% charge

Now, this probably isn't too useful for batteries that you are actively using - however, if you have spare lithium batteries lying around that you aren't using at the moment you might want to drain the charge to about 40% and zip them up in ziplock bags and put them in the fridge until you need to use them (check it once in a while to make sure they haven't drained to zero charge because that can kill them).

Also, this means that you should avoid letting your Li-ion batteries get hot unnecessarily, like leaving them in a hot car in the summer.

This is a good reference http://www.batteryuniversity.com/parttwo-34.htm

Others have given more technical details, but for a real-world example; the iPod Classic charges to 80% in 2 hours, and 100% in 4. The other iPods are the same, except the nano charges to 80% in 1.5 hours and 100% in 3. Any lithium ion battery should be charged in a similar manner.

You can find more information about charging LiIon batteries here.

OK, I did a quick search and yeah, the cheapest chargers are fixed current with a timer to prevent overcharging.

But for a few bucks more you get a charger with basic peak detection.

Back when I was in to RC cars 15+ years ago, my first charger had a basic timer. 15 minutes from a dead pack (standard charge) resulted in a slightly warm NiCd pack. Any longer and it heated up quick.

My limited experience with NiMH SubC packs more recently had them fairly warm after full charge on a peak-detection charger charging at about 1C. Didn't charge any longer than that to see how hot'd they get.

Why anyone would spend $50-$100 on multiple good quality NiMH battery packs and then not spend about the same on a decent peak detection charger defies logic. A good charger maximizes performance of the pack and battery life. Heck, I even went and looked at Tower Hobbies - a basic timer charger costs $25 - a basic peak charger costs $35. I suspect only the uninformed buy the timer chargers these days.

Most of my experience with rechargables these days lie with AA and AAA size cells. I've got a handful of old Eveready NiCd cells (out of a dozen or so) that have been used and abused for about 15 years or so.

Capacity has dropped about 10% from their rated capacity for the ones that still work. The dead ones stopped holding charges for more than a couple days and developed internal shorts (common death scenario for NiCds after being stored dead or forced into reverse voltage when used as part of an imbalanced pack).

The NiMH cells I've used have proven to be much less durable and seem to be much less tolerant of abuse. They have had a much higher rate of capacity loss. I've had probably half my older batch of cells stop holding charges. The other half have lost between 20-30% of their original capacity. Not sure if it's the cheap cells (Powerex, primarily) or NiMH technology (batteryuniversity.com and wikipedia both seem to indicate that NiMH cells are less durable than NiCd cells).

Now I only buy low-discharge NiMH cells. Because your typical cell will basically self-discharge between 20-30% a month, this leaves them useless after only a couple months of storage and dead after 6 months or so. And remember that storing a dead cell also leads to early cell death.

The low-discharge cells will retain about 85% charge after a year and 70% after two years meaning that there is little danger of cells fully discharging and the cells will be ready to use without having to wonder how long ago you recharged the cell. They are also much better for low current applications like clocks and remote controls where battery life won't be determined by how well the cell retains it's charge, but it's actual capacity.

I also use a good digital charger (Powerex MH-C9000) which I can use to monitor the cell's capacity and adjust the charge rate according to the type of cell being charged, as well as easily determine when a cell has reached the end of it's useful life and put it aside for recycling.

There are a ton of variables that determine battery life, but to say that it relies mostly on your charger is not true when even the most basic charger these days uses peak detection and thermal monitoring to stop charging.

NiMH batteries will _always_ get warm when charging at a decent rate (and most cells like to be charged at a rate somewhere between C/2 and C to get reliable peak detection), because charging them is only 70-80% efficient. The rest goes into heat. If you continue pumping current into them after full, then yes, they heat up quickly.

NiCd batteries only heat up significantly when you continue to charge them after they are full, or you charge them at very high currents.

The #1 killer of typical batteries is letting them sit around dead or pushing them into reverse voltage by draining a pack too far. They like to be stored with at least some charge in them, but too often they end up sitting around for a year or two in between uses and too often they end up sitting dead which kills them. Lithium based cells are so bad that if you drain them completely, you can not revive them, so they typically have a small circuit on them which monitors cell voltage and disables the cell when too low.

There is a ton of information on proper care of batteries including charging here at BatteryUniversity.com including information on what types of behaviour kills certain types of cells the fastest.

Hmm...just struck me as a strange statement. Doesn't everyone put their phone on the charger overnight? It just seemed the common thing for me to do (not an iPhone owner)...I figured everyone charged or 'topped off' their phone nightly.

They should, but most people don't. They get a bit of a thrill seeing if they can beat their old record for the number of days without charge. They also enjoy forgetting to charge it, and then having a dead phone. It's the little things in life ...

Seriously, though, it's mainly because phone salespeople are incredibly ignorant about Li-ion batteries. They always tell you that you should charge from empty -- whereas in reality, it's the worst thing you can do for a Li-ion battery (see, for example http://www.batteryuniversity.com/parttwo-34.htm). Mind you, maybe it helps them sell replacement batteries?

My friends look at me like I'm mad when I tell them to charge their phone every night. It's funny how, even though it's been years since anyone's used a NiCad rechargeable, the "charge from empty" mentality still holds ...

Wind, water, and solar plants may have low efficiency for turning energy into electricity, but the energy required to do that is free, unlimited, and does not directly pollute, so therefore is irrelevent.

Wrong. *Nothing* is irrelevant. Wind and solar have huge capital costs relating to all of the mining, processing, and labor that goes into them. Think giant towers of steep pop out of the ground without extensive mining and very dirty smelting operations, for example? The environmental cost of wind and solar is certainly notably lower than coal, but it *is* relevant. They also take up land that could otherwise be wilderness (especially solar, which can't pair with farming like wind can).

Hydro ("water") is the worst. It takes up huge amounts of land -- often ten times as much as the equivalent amount for solar generation in a sunny location. It destroys what are often some of the most scenic and environmentally sensitive areas in a country. Consider the Xolorado, for example -- an aquatic oasis in the middle of arid lands that used to even have otters living in it before we dammed the heck out of it and destroyed canyon after beautiful canyon. And to top it all off, *hydro causes global warming*. Hydroelectric plants lead to organic matter decaying anerobically instead of aerobically, which means methane, not CO2. Methane is a far worse greenhouse gas than CO2.

Efficiency ALWAYS matters.

I'm NEVER going to suggest we use coal or other fuel to compress the air for air cars, nor would I for electric cars either

It's better for the environment to run an electric car from coal electricity than a gasoline car burning gasoline. By a good margin. It's notably *worse* to run an air car from coal power.

The direct efficincy of stored energy to engine power is near 100% for air cars.

~90% or so. It's getting the energy stored that's the problem -- 10-15% efficiency from garage or onboard-scale compressors.

Your numbers on electric motor efficiency are also WAY off. Yes, motors can operate at those efficienies, but only under constant and predictable (ideal) torque and RPM. In the field, they almost never come near those ideals. They do much better (60% or so efficiency for electric

Sorry to be blunt, but you simply have no clue what you're talking about. Start reading. The most efficient electric motors are about 95% efficient. 85-90% is more typical for an electric car in standard driving conditions.

combine this with distance loss of poewr over high voltage lines

A) Air compressors have the exact same loss.
B) Once again, you demonstrate your ignorance. In the US, transmission losses are only 7.2%.

battery charge loss (heat when charging)

0.1% for li-ion.

battery depreciation (loss over time)

Virtually none with modern automotive li-ions (nanophosphates, titanates, spinels, etc).

and discharge loss (bettery efficincy)

Also 0.1% (see above link).

the other problems with electric cars are safety

That's funny coming from an air car advocate, given that compressed air has the fastest energy discharge in disaster conditions, faster than even hydrogen.

LiIon batteries explode

Automotive li-ions (titanates, nanophosphates, spinels, etc) do not.

capacitors can kill instantly

So can an exploding air tank. Both are "accident situations", but the former requires either new laws of physics or the casing to break and move out of the way, all of the engine components between it and you to move away, terminals to suddenly run into you or something you're sitting on, all without the fuses melting.

they're complex and expensiv

. If you use your figure of 900MJ, and charging is 90% efficient

There's your problem right there. Li-ion batteries have a charge efficiency of around 99.9%; you're two orders of magnitude off. Even if you go off by an order of magnitude and say 99% efficient, assuming a specific heat of 1J/g*C, with 7.2MJ/kg, that's only a 72 degree rise in temperature over 5 minutes or so (240W of heat), which a cooling system could easily manage (your computer case fan probably dissipates more heat than that). With the actual 99.9% efficiency, it's a 7.2 degree rise in temperature and 24W of heat, respectively.

The other issue is that we (US) have nowhere near the generation capacity to handle a nation full of electric cars.

Another widespread false concern. The fact is that the US has significant surplus generation capacity at night, more than enough to begin the transition (it's not like everyone collectively throws out their vehicles and switches at once). Furthermore, it's much *cheaper* to build new electricity production infrastructure than it is to produce gasoline production infrastructure. And, for gasoline-powered cars, you have to keep producing new gasoline-production infrastructure even when gasoline demand remains constant since oil fields run dry. You're just replacing one type of infrastructure demand with another -- one that's easier to meet to boot.

From here:

"The charge time of most chargers is about 3 hours. Smaller batteries used for cell phones can be charged at 1C; the larger 18650 cell used for laptops should be charged at 0.8C or less. The charge efficiency is 99.9% and the battery remains cool during charge. Full charge is attained after the voltage threshold has been reached and the current has dropped to 3% of the rated current or has leveled off."

It's all about size, weight, and the abusive charge cycle that laptops and cellphones are required to go through. From what I've read, the thing that really stands out for lithium batteries is the lack of cell memory. Here's a link comparing 4 battery types: http://batteryuniversity.com/partone-21.htm

I looked up a few details and found this article, which - if correct - seems to provide a lot of information.

It appears that there are many factors in lithium battery life. Deep-cycling is not good, but neither would repeatedly charging the battery when it is not necessary (using up charge cycles). It also mentions an often-forgotten factor, heat, which as well could be related to overcharging, or constant charging.
As it says in the article "Removing the battery from the laptop when running on fixed power protects the battery from heat."

Perhaps a happy-medium would to charge when it's about halfway down?

It seems to me that the best method would be to have a quick-switch circuit which would combine fixed-power, a capacitor, and the battery. When plugged into wall-power, the battery is charged up and then disconnected from the circuit when around full. The circuit then runs off fixed-power which runs through a capacitor. In the event of a drop or disconnection of fixed-power, the circuit could stay "alive" long enough on the capacitor to switch back over to using the battery. I'm not sure if anyone does this though, but depending on the needs of the capacitor it might be a good fix... it shouldn't have to run on the cap for more than a second or two before swapping over to battery-power.

Lithium-ion batteries (and all lithium-based batteries) will degrade 20% in storage capacity from the manufacturing date when stored at 77F regardless of use (1). Different storage temperatures result in different storage capacity degradation. Charging or discharging will not reduce the storage capacity unless it significantly raises the battery temperature, i.e. quick chargers.

I have searched everywhere to find manufacturing dates for my laptop batteries, but everyone seems reluctant to list that information. Lithium-based batteries really need a "born on" date.

1

It looks to me like generating H2 via electrolysis of water is in the same general ballpark effenciency wise as charging/discharging batteries (both somewhere in the 50% range).

Lithium-ion batteries are pretty close to 99.9% efficient. The only way hydrogen is going to beat that is if we hit a shortage of lithium and need a different sort of battery, or hydrogen can somehow become an energy source rather than energy storage. Harvesting pre-existing sources of hydrogen (like Jupiter's atmosphere) would work as an energy source. But if space flight is cheap enough to harvest hydrogen as an energy source, we'll already have access to a bunch of other clean energy sources.

Um? That pretty much goes against everything I've seen written about Li-ion batteries. (And my experience with them as well.)
http://batteryuniversity.com/parttwo-34.htm

Any time I read about a lithium battery catching fire, I always wonder why the reporting sources don't educate the public about the inherent danger of a lithium fire, specifically the fact that water really isn't a good thing to be putting on it.

To learn about the different chemistries:

http://batteryuniversity.com/

I've found NiMH to be the best balance for all my applications.

I've had good luck buying NiMH in bulk from this company:

http://www.shorelinemarket.com/

I've purchased AA and AAAs in bulk from them (Tenergy AAs and Powerizer AAAs). While they aren't the highest capacity batteries available, they are pretty close, and I haven't been able to beat the price per cell on comparable batteries or the price per MaH.

The AAs seem to do a bit better in high-drain, as they seem to bleed a full charge in about four-six months, which means something that might run practically forever on a set (like a transistor radio you don't use often, or a small scanner), usually won't eat the batteries before they eat themselves. But they've done really well for me.

I'm not real happy with the Powerizers. They seem more like 400-500mah than 850, but alas, I can't really test them. I'm tempted to buy some of the Tenergy AAs to try, but unfortunately I've already got a bunch of the Powerizers.
I also purchased their 10-position AA/AAA charger/discharger. It works fine, but makes this annoying buzz every second or so as it charges and discharges, I'm assuming because of cheap components. Invest the extra bucks for a nice Maha.

Anyway, read up at battery university before you go making any purchases. There is a lot of good info there. Just keep in mind they are operated buy the guy who runs Cadex.

First, The distinction of Li-Poly from the general chemistry of Li-Ion is in the electrolyte. Instead of a liquid or gel electrolyte, the Li-Poly cell uses a thin sheet of conductive polymer doped with ionic compounds. Now while this polymer electrolyte has less mobility than a liquid, resulting in a lower energy density (J/cm^3) and power density (W/cm^3), in practice the manufactured shapes can be more complex than the coin or cylindrical shapes imposed by liquid electrolytes. Therefore more "battery cell" can be stuffed into otherwise unused volumes, and in many applications this maximizes the effective energy density beyond what can be achieved using cylindrical cells.

Second, any Lithium chemistry cell using a Cobalt-alloy cathode (virtually all of them on the market today) is subject to a thermal runaway condition if the internal cell temperature exceeds 130C. This includes Li-Poly cells.

Valence corp has patented a Lithium-Iron-Phosphate cathode chemistry that has less energy density, similar to NiCd, however the change to a Iron cathode eliminates the thermal runaway possiblity, making the cells much safer. These will soon be available commercially from DeWalt as battery packs for their cordless power tools. Here is a press release... note that Valence later bought the company referenced therein, A123 Systems. (I wonder if there's been a delay somewhere - DeWalt was marketing this much more heavily just a few months ago, now you have to do a search on their site to find any reference of it.)

Another company, Altair Nanotechnologies, has patented a Litium Titanate Spinel anode technology that also claims to eliminate the risk of fire and improve on both the Energy Density and Power Density of vanilla Li-Ion. However they have yet to actually deliver cells (to me anyway, despite many requests). And this chemistry is not exclusive to the Iron Phosphate cathode, meaning someone with all of the proper patent licenses could combine the two and make a high energy-density, non-exploding laptop battery that does even better than the Li-Poly battery I'm using in my MacBook Pro right now.

Finally, here's a link to the "Safety Concerns" page of the "Battery University" site which is an excellent user's reference for Li-Ion secondary batteries, among others. And here is a link to a Valence Corp white paper that describes their LIP cells. Lastly, here is a PDF of Altair Nano's marketing material describing their claims of safety advantages their Titanium spinel material offers to commercial batteries.

So what about the batteries?

Notice that the WrightSpeed website doesn't tell you anything about battery life.

Here's a link to a website for engineers that deals with battery issues: http://www.batteryuniversity.com/parttwo-34.htm

Check out the data for ageing due to storage temperature and charge/discharge rates.

Not pretty is it? Leave your car out in the parking lot and its batteries get trashed.

And that 100 mile travel rating is for new batteries. It's going to be 80 miles next year.

How many years will you wait before you relace your batteries?

The T-zero uses 6,800 'laptop computer' batteries. You do the math on that.

Some lithium-ion batteries feature an ultra-low voltage cut-off that permanently disconnects the pack if a cell dips below 1.5V. A very deep discharge may cause the formation of copper shunt, which can lead to a partial or total electrical short. The same occurs if the cell is driven into negative polarity and is kept in that state for a while.

Manufacturers rate the lithium-ion battery at an 80% depth of discharge. Repeated full (100%) discharges would lower the specified cycle count. It is therefore recommended to charge lithium-ion more often rather than letting it down too low. Periodic full discharges are not needed because lithium-ion is not affected by memory.

The reason why laptop *appears* to have battery capacity gauges that don't like being left on A/C power for a couple of months is not the gauge, it is the battery.

Lithium Ion batteries works poorly in constant full charge conditions and in hot temperatures. Their effectiveness degrades in heat and constant full charge. And guess what? A constant plugged in laptop has BOTH! Heat from the computer and full charge all the time. So a laptop left plugged in for months will kill the battery fast with the heat it generates and the constant charge of the battery.

Read here: http://www.batteryuniversity.com/parttwo-34.htm

Cute try, but you haven't seemed to figure out the difference between marketing specs and actual tests. Yes, marketing says they should last about 500 cycles so heavy users should generally get about 2-3 years out of them. (Obviously some people will get more.) But the reality is that many people have much less actual time with them and have even sued over it.

As for the total hours, sure some people can get up to 12 hours (often only in the first year) on the generation 4 and 5, but if you read some of the above you'll see some as low as 4-5 hours, and often 8 hours is a typical normal accomplishment. You'll even notice some of the above links report the iPod mini is supposed to get 12 hours but testing suggests it only gets about 7 hours.

We can argue about actual numbers and conditions like crazy, but the point is that real people are getting less than the marketing suggests and a good number have general battery problems.

As far as replacement, yes, you can crack it open yourself using 3rd party battery sources, but a proper battery replacement (they aren't made to be opened) costs $99 from Apple (see above link).

Even more importantly, the actual dollar and length of life is not really the main issue. The point is that iPods have battery problems. It's easy to find all over the internet. While this isn't a big problem with some people, it certainly means that not only "dumbfucks" (as the grandparent post said) have objections to the iPods and there are legitimate reasons to believe that they aren't the best.

The only reason you should fully discharge a battery is to calibrate the battery meter. Full discharges have a negative effect on battery life. http://www.batteryuniversity.com/parttwo-34.htm

Unfortunately, Li-Ion Batteries degenerate with time, from the date of manufacture, regardless if they are used or not. A Li-Ion battery will only perform well for a 2-3 years.

See: www.batteryuniversity.com for more information. There is also great advice for dealing with "Battery Gauges" (They calibrate on a full discharge)

The lithium ions are very reactive(hence them being part of a energy storing *BATTERY*). As the article states, messing with lithium batteries (especially without the protective circuitry) can result in fires at the least with a mild possibility of explosion.

1) Overcharging results in outgassing. (See picture at end of http://www.batteryuniversity.com/print-parttwo-32. htm for a picture of a Li polymer battery, which is considered safer than a standard Li-ION). If the safety valve on a standard cell doesn't open(should be rare), you'll have a mini pipe-bomb on your hands.

2) A mid-sized fully charged laptop battery pack usually stores >70Watt-hours of energy. If this is shorted without the battery protection, a battery can probably dump a good fraction of its total energy in a couple minutes. A few hundred watts will then cause the previously mentioned pipe-bomb effect as well as igniting anything combustible in the general vicinity.

So - listen to the article and don't screw with these styles of battery without educating yourself first.

A while ago I stumbled across this site called Battery University, which has a lot of detailed information about how various kinds of batteries work and how best to make use of them. Not sure if this is relevant, but just wanted to toss that into the conversation.

How to prolong lithium-based batteries.

The LiON battery will still hold a charge, but they eat-themselves just as a matter of their functionality. They are a consumable battery just like an alkaline.

I've always wondered why LiON batteries aren't required to be rated for total number of ampere-hours of use.

Here's a article describing their expected lifecycle.

An excerpt:

------

Aging of lithium-ion is an issue that is often ignored. lithium-based batteries have a lifetime of 2-3 years. The clock starts ticking as soon as the battery comes off the manufacturing line. The capacity loss manifests itself in increased internal resistance caused by oxidation. Eventually, the cell resistance will reach a point where the pack can no longer deliver the stored energy, although the battery may still contain ample charge. Increasing internal resistance is common to cobalt-based lithium-ion, a chemistry that is found in laptops and cell phones. The lower energy dense manganese-based lithium-ion, also known as spinel, maintains the internal resistance through its life but loses capacity due to chemical decompositions.

Yep - "The battery prefers a partial rather than a full discharge. Frequent full discharges should be avoided when possible. Instead, charge the battery more often or use a larger battery." http://batteryuniversity.com/parttwo-34.htm

Don't know where you're getting that 100 cycle lifetime from. I think these people would like to have a word with you regarding a litte chemistry and physics.

Disclaimer: I don't work for them and I'm about as close as it gets to being a 'crazy eyed bandit' when it comes to discharing my laptop battery. It has served me for 18 months before crapping out and that's with multiple deep discharges per day. A lot more than 100 discharges...

Looks like I need to go catch up on reading some Nerdular Nerdance...

Of course how long the charge lasts depends on what it's powering - I'm assuming you're referring to laptops. I have a LiIon cell in my mp3 player which lasts 16 hours and one in my phone which lasts several days - but I'm sure you understand that.

Also - check out this link (and the rest of the site) for great info on various kinds of batteries. It mentions than in fact LiIons have a per-charge lifetime _and_ a simple age based lifetime. They reckon most LiIon cells will last 300-500 charges, or 2-3 years, whichever comes first.

Check out the Battery University for the answers to all your battery questions.

iPod Battery FAQ

http://ipodbatteryfaq.com/

Q: Is the iPod's battery replaceable?

A: Yes. Apple has an official battery replacement program for $99. You send your iPod in (any model iPod), and Apple will replace the battery for $99. AppleCare programs for iPod will also soon be available in Europe.

Q: Is the iPod's battery user-replaceable?

A1: Yes and no. The iPod's case is not designed to be opened, so, in that respect, it's not what would generally be referred to as "user-replaceable". But, the case can be opened, and there are several third parties that offer replacement batteries for the iPod, such as iPodBattery.com (instructions, with pictures: original, non-"dockable" iPod, new, slim "dockable" iPod) and PDASmart, for as low as $49. Some will even do the replacement for you if you send it in.

A2: TechTV's Call for Help has a story, with video , discussing and demonstrating replacing an iPod battery (the video was produced before the Apple service options were available).

Q: What is the iPod's warranty? Does it cover the battery? Is there any way to extend it?

A1: The iPod warranty is one year. It does cover the battery.

A2: You can extend the iPod's warranty, including battery coverage, to two years with AppleCare Protection Plan for iPod. Numerous retailers, such as Best Buy, CompUSA, Circuit City, etc., also have very inexpensive extended warranty coverage available for iPod. Often these plans simply replace the product with a comparable new unit.

Q: What's the deal? Does Apple think the iPod is disposable?

A: No. Like all Apple products, the iPod is engineered to last. This is why Apple is consistently ranked number one in product quality and support by leading consumer groups, such as Consumer Reports.

Q: I heard that the iPod's battery only lasts 18 months, and then you have to buy a new iPod! Is that true?

A1: NO! The vast, vast majority of even the earliest iPods, now over two years old, continue to function just fine. Some iPods, however, have had issues with batteries. Lithium ion batteries are only good for 300 to 500 charge/discharge cycles (more). For this reason, certain customers' usage patterns may cause the batteries to degrade, or fail, sooner than others.

A2: If the battery does fail, and the iPod is no longer under its original one year warranty or $59 AppleCare Protection Plan for iPod, or any of numerous third party service plans, you don't have to buy a new iPod. You may replace the battery yourself for as little as $49, or have Apple perform the replacement for $99.

Q: Why didn't Apple use better batteries?

A: Apple uses the best lithium ion battery technology available from leading battery manufacturers. This is the best, most cost effective battery technology available given the requirements of the device.

If users are complaining about it, it's a flaw. Because the flaw can not be fixed without significant re-engineering, it's fundamental.

Um, no, not everything that is complained about is a flaw. This issue affects a very, very small portion of iPod owners. The second part of that statement is rendered invalid. Additionally, there is an official program to replace the batteries, if need be, as well as numerous ways to do it yourself. Just because the Neistat brothers couldn't do it means nothing. The instructions are here, with pictures: old, new.

The vast, vast majority of iPod owners' batteries will last the life of the product. These premature failures are fringe cases. Lithium ion batteries are good for 300 to 500 charge/discharge cycles. If you are a heavy user, i.e., recharging an average of once a day or more, and using the unit daily, AND are always running the unit down to completely dead (a big no-no for all lithium ion batteries) you could conceivably be in a situation where your battery has degraded prematurely. But the plain fact of the matter is that almost all first generation iPods, some of which are over two years old, continue to function just fine, and will continue to do so.

Other manufacturers are doing the same thing: integrating batteries on hard drive-based players specifically for the purpose of reducing the size.

Apple, your customers are speaking. Are you listening?

Apple, an extremely small, vocal percentage of your customers are making an issue out of nothing (since there are several reasonable ways to replace the battery, including official ways through Apple itself) - er, wait, some people who don't even own iPods, but just relish in anything negative related to Apple - are you listening?

Oh, wait...you already did.

(Note: if Apple's rumored new "cheap" iPods have easily accessible user-replaceable batteries, it won't be because of slashdot, the Neistat brothers, or "bad press", because the products have been in development for ages before this ever even came up.)

(Not in relation to the mini-iPods, as I don't know their specifications, but there seem to be enough idiotic battery posts, so...)

Q: Is the iPod's battery replacable?

A: Yes. Apple has an official battery replacement program for $99. You send your iPod in (any model iPod), and Apple will replace the battery for $99.

Q: Is the iPod's battery user-replaceable?

A: Yes and no. The iPod's case is not designed to be opened, so, in that repsect, it's not what you would generally refer to as "user-replaceable". But, the case can be opened, and there are several third parties that offer replacement batteries for the iPod, such as iPodBattery.com (instructions available at that link) and PDASmart, for as low as $49. Some will even do the replacement for you if you send it it.

Q: What's the deal? Does Apple think the iPod is disposable?

A: No.

Q: I heard that the iPod's battery only lasts 18 months, and then you have to buy a new iPod, is that true?

A: NO! The vast, vast majority of even the earliest iPods, now over two years old, continue to function just fine. Some iPods, however, have had issues with batteries. Lithium ion batteries are only good for 300 to 500 charge/discharge cycles. For this reason, certain customers' usage patterns may cause the batteries to degrade, or fail, sooner than others.

A2: If the battery does fail, and the iPod is no longer under its original one year warranty or $59 AppleCare Protection Plan, or any of numerous third party service plans, you don't have to buy a new iPod. You may replace the battery yourself for as little as $49, or have Apple perform the replacement for $99.

Q: Why didn't Apple use better batteries?

A: Apple used the best lithium ion battery technology available from leading battery manufacturers. This is the best, most cost effective battery technology available given the requirements of the device. The lithium ion batteries Apple uses are no different than lithium ion batteries used by anyone else. The battery should last most normal users several years.

Q: Why doesn't Apple make the battery easily replaceable, then? Or use different batteries, like AA?

A: Because if they did either, the size of the batteries and/or the access panels and mechanisms required to access the battery would make the unit significantly larger than it is, likely by several milimeters in thickness at a minimum, and it may possibly affect other dimensions as well. It was an engineering decision to use an integrated battery; if it were not integrated, the unit would not have the small, sleek form factor that makes it so attractive. Additionally, the iPod's battery is indeed replaceable, as has been discussed above.

Q: Well, no one else does that!

A: Wrong. Prime example: Dell's new DJ portable music player uses an integrated, non-user-replaceable lithium ion battery, just like the iPod. Dell also has no plan or program to replace batteries outside of warranty at this time.

Q: But, Apple only released their battery replacement service because of all the bad publicity from the Neistat brothers' video.

Wrong again. Apple released the battery replacement program as early as November 14. ipodsdirtysecret.com was only registered on November 20, and started being heavily publicized on November 21. Additionally, Apple had been planning the battery replacement program for months - these types of service programs don't just happen overnight - before Casey Neistat even had his first contact with Apple. The video campaign had nothing to do with Apple's rollout of the battery replacement program.

The site batteryuniversity.com discusses many aspects of recargeable batteries like cycle time, charge/usage behavior, memory behavior and so forth.

It helped me a lot to understand the different types of batteries available and for what application which battery is best suited.

Cheers

Bullshit this is not. Lithium Ion batteries (like the ones used in the iBook, as well as most any other laptop made recently) have a half-life of about 300-500 charge cycles.

If you are not charging your laptop every day, then these cycles will last you years. However, if (like me) you end up seeing several charges a day, you can easily kill a battery in a matter of months.

I've never used the IBM 600 series laptops. Any chance those aren't even Lithium Ion batteries?