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Rechargeable Batteries - Yes or No?
TheFifthElephant asks: "I currently use quite a few devices that require various size batteries and I feel horrible just tossing them when they die. I saw a recharger at a retail store today and was thinking to myself how much waste it would reduce by using rechargeable ones. Which units have you used happily and/or which units have you heard of/read about satisfying someone else? Are the more expensive units better? What chemical rechargeable batteries last the longest/recharge the most?"
These batteries kick serious booty. In my digital camera, a single charge outlasts even the best disposable batteries by a factor of 2 or 3. In about a year I've already saved more in disposable battery cost than I spent on the charger and cells.
Definitely worth the investment. I have Panasonic brand, but only because that's what they had at Costco. I doubt that there is a big difference between brands of similarly-rated cells.
My amazing wife - Artist, Author, Philosopher - Laurie M
NiMH batteries are great but they have the downside of losing charge very quickly "on the shelf" so you can't keep a bunch of charged MiMH batteries ready to use.
You know, you can recycle your dead batteries, right? When I worked at Radio Shack a long time ago, we took in dead batteries and sent them off to be recycled. I'm not sure if this was just my store, or a company wide thing, but there are free recycling services out there.... so don't throw them away!
Imaging-resource.com did a great review of a ton of rechargeable batteries. The electronics geek in you will enjoy his breakdown of how he conducted the tests.
C - A language that combines the speed of assembly with the ease of use of assembly.
Da Blog
- Buy a good charger. Cheap ones can fry batteries, take longer to charge, and can go up in smoke easily. Also, make sure it can charge NiMH batteries as well as NiCDs; if you have high-drain devices like digital cameras, then you want NiMHs, and probably don't want to pay for a new charger for 'em. Expect to pay $30-$50 USD for a decent one.
- When you buy batteries, look at the milliamp-hour rating. That's the capacity they can hold: for example, an 1800 mAh AA could supply (theoretically) 1 mA for 1800 hours, 1800 mA for one hour, or anything in between. While mAh ratings do tend to be stretched a bit (the tests are performed under the most favorable circumstances possible), it's the best guide you can get to how long the battery will last in the device you plan to use.
- Don't buy more battery than you need. Your TV remote probably doesn't need expensive 2200 mAh NiMHs, so put in cheaper 800 mAh NiCDs.
- You'll be better off buying online than anywhere else. I've had good luck from several companies, but note that the "Energizer" branded batteries are relabeled and marked-up generics; you can get better batteries, cheaper if you go with other companies.
- Get extra batteries. You should have a few sitting around for when something important goes dead; don't just buy what all your devices need. Get a few extra of each type you use, or just keep alkalines around to use while recharging.
- Don't be too hard on your batteries. Many good chargers have a "fast" and a "trickle" setting; don't use the "fast" setting unless you absolutely can't wait overnight. Fast charges are hard on batteries; once or twice won't hurt much, but repeated fast charges can cause a significant drop in total battery life.
- Finally, if you have some high-drain devices and want to get more battery life, try hacking something onto the AC adaptor. A good guide to doing this with your digital camera is here; the principles are pretty much the same for anything else that has an AC adaptor socket.
Good luck!That's it. I'm no longer part of Team Sanity.
There's also this Battery Shootout ranking system, skewed towards small portable electronic device effectiveness.
Da Blog
I use NIMH in my digital Camera (an older Olympus D-460) and they are great. I keep two sets in my camera bag, the NIMH and a standard high-quality alkaline set, Normally I use the NIMHs till they are low (which can be several days of moderate camera usage) and then swap in the standard batteries and continue till I can get the NIMHs recharged. Recharging takes a few hours but once charged they are ready for hours more work. With this the 'normal' batteries last for a few months of occasional use.
If you are using them on something you depend on (camera, camcorder, etc.) It would be prudent to have a set of high-quality standard cells for backup like I do.
NICADs historically develop a memory problem and may not hold much of a charge later on (not that they hold much in the first place from my experience). NICAD technology may be different now, so choose your rechargable batteries sensibly.
"Enjoy what you're doing! If it becomes drudgery, you're doing it wrong!" - Jim Butterfield
About chargers, understand that there are two types out there; timer controlled and -deltaV controled.
You want the -deltaV controlled, which monitor the voltage on the battery to sense when they're fully charged. The timer controlled chargers, will overcharge the battery, and nothing kills batteries like overcharging.
Now it turns out that for low amp applications, even a simple charger will get enough performance out of the batteries, but for more serious applications such as digital camera, a real charger could tripple the number of cycles you'll get out of the batteries.
Also, watch out for 'micro processor controlled.' While all -deltaV chargers will have that on them somewhere, it may also mean timer controlled (as in there's a micro processor keeping time somewhere).
There was a good test this spring in the Swedish equivalent of Consumer report, but unfortunately it's in Swedish (and you have to be a subscriber). The noteworthy point was that not all -deltaV chargers are created equal, one undercharged, so you may want to check around. Expect to pay serious money for a serious charger. The good ones in the test were $100-$200 in Sweden, you'd pay perhaps 50%-75% of that in the US (I don't really know the battery charger market).
P.S. Use NiMH. Better for you, and no memoy effect. With a -deltaV charger you can easily top them up if you've had them on the shelf for a while (they'll lose their charge in a couple of months when stored).
Stefan Axelsson
NiCd and NiMh batteries have discharge curves closer to that of a standard Alkaline AA...
But Alkaline batteries have high internal resistance, so they're not terribly useful in high-current devices like my Kodak digicam. That high resistance causes the batteries to heat quickly, and because resistance increases with heat, it gets worse the longer you use the device. The voltage drop across the resistance causes the output voltage to drop, and before long it can drop below a useful voltage. In high-current devices, NiMH and NiCd batteries work much longer than alkaline batteries, in part because they don't heat as much.
This isn't just theory; I've tried alkalines in my digicam, and they don't last for more than a handful of photos, not nearly as long as my usual NiMH cells. So I can use alkalines, but only in a pinch. For low-current devices like a CD player, alkalines may last as long as NiMH or NiCd, but when they're done you have to throw them away.
I replaced over 100 batteries used in our household (three daughters, geek father) with NiMH. No problems at all. I get the next to highest mAh rated batteries from Thomas Distributing (just a happy customer) and I use an Altek 5798 charger. The tri-state LED's give a good status on when its done charging.
I had a few go bad over the past few years, but I know several sets have had hundreds of charges.
The last AA set I got were 2000 mAh and they are great in my Fuji digicam.
www.thomasdistributing.com - don't let the 'web designer on acid' interface bother you, they have always had the best price and reasonable delivery. I even like the 'free gifts' (synth chamois car cloth, plastic battery holders).
Hope this helps!
Radio shack has a nice page about different batteries.
Is operating temperature a concern? NiMH batteries are not so good in low temperatures, so don't use them in a GPS on your Everest Expedition.
What about space/weight/charge density? Lithium Ion batteries have a higher energy density than NiMH and NiCads, but they require more intelligent (read: expensive) chargers, as they are often microprocesser controlled.
Current Drain? NiCads can deliver more current than NiMH batteries.
Access to power supply? Weight and size of chargers? NiCad batteries are the easiest (after Lead Acid) to recharge, so the charger could be lowcost and small sized. You can charge a NiCad quite well with just a dc power supply and an appropriate voltage dropping resistor, just make sure that you time the charging to match the capacity. You can't jury-rig chargers for Li Ion batteries and you have to be very careful for NiMH cells (you really need to detect the voltage drop these guys display when nearing charge completion and trickle charge from that point onwards).
Also, contrary to what others have posted, not all batteries of the same kind are created equal. Stick to name brands (Sanyo batteries have been very good for us) - they tend to last a little longer. Maybe they have more pure electrolyte or electrodes?
Avoid rechargable alkalines. It will end in tears.
Good luck with your decision.
"The big question in our lives is how to be at the same time a hedonist and in a hurry" - Alain Ducasse (?)
A great deal of the raw materials for NiMH batteries comes from China (and Russia), regardless of what the "made in ..." sticker says. (See http://ovonics.com [ECD, the NiMH patent holder] for more info.)
:)
So, if you buy NiMH, you don't have a lot of choice in the matter. This is NOT to suggest avoiding NiMH, which is a superior battery in many situations - just to inject a note of realism.
As for the original poster's question, surely there is a website out there with vast amounts of statistical data on the various brands (and types!) of batteries?
I like NiMH as it is relatively easy (and safe) to recycle. However, keep in mind that NiMH can lose up to 2% of its charge per day sitting on the shelf. NOT a good choice for that emergency flashlight.
If you're not living on the edge, you're just taking up space!
4) Actually, you need a "push mower" like the old days. Save money and slim that fat ass of yours.
Actually, I have a "push mower" (it's called a reel mower) like the old days. It's actually lighter to push around than a regular gas mower since there's no engine, with the added benefit of getting to experience the "fresh cut grass smell" the entire time rather than only after you're finished. The only downside is that you can't let your lawn get out of control. You have to keep up with it because the mower won't cut grass that's longer than four inches or so.
More than you ever wanted to know about battery tech. Keep an eye on the emerging Lithium Polymer batteries @ roughly 3X the current NiCd and NiMh power/weight and power/size batteries. I use them in my micro R/C helicopter instead of the oringal NiMh and get 3X the run (was 5 now 15 minutes) with less than 1/2 the original battery weight (1.75oz vs 3.75oz). These are gonna be cost effective in the next 10 years or so, making a 100 mile range EV very easy and cheap. This is what they are using in the current solar racers. Environmentally friendly as well! Oh the original question? 2000mah NiMh all the way.
The amount of water used in the process of makeing diapers exceeds the amout of water when you wash diapers (if you fill the machine up). The a weight of garbage from one average kid using diapers is 1000kg. The energy from transporting the garbage, makeing the diapers and transporting the diapers to the shop exeeds the energy to clean the diapers by serveral times. An average kid uses 5000diapers. That is about $1500. A set of cloth diapers costs about $35. We have used cloth diapers for both our girls. It was really good and as they feel that they are wet when they pee, they stopped using diapers a lot sooner then the other kids at kindergarden.