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Company Extends Alkaline Battery Life With Voltage Booster
New submitter ttsai writes: Batteroo is a Silicon Valley company preparing to release its Batteriser product in September. The Batteriser is a small sleeve that fits around alkaline batteries to boost the voltage to 1.5V. This means that batteries that would otherwise be thrown into the trash when the voltage dips to 1.3V or 1.4V could be used until the unboosted voltage reaches 0.6V, extending the useful life of a battery 8x, according to the company. This product has the potential to reduce the number of batteries in landfills as well as increasing the time between replacing batteries. The expected price of the sleeve is $10 for a pack of 4 sleeves.
The article presents some info that just isn't quite right. The device will probably be useful but not nearly as good as they claim. Instead of 8 or more to one times the typical battery lifetime, it will be more like two times. Google "joule thief" and read the articles and comments carefully. This device works the same way; just in a compact package.
"Almost every wise saying has an opposite one, no less wise, to balance it." - George Santayana
This has been around for years. A device from last year uses the same joule thief circuit.
Even those who arrange and design shrubberies are under considerable economic stress at this period in history.
Carbon-zinc and alkaline (MnO2) batteries will go to complete discharge without any danger. You're thinking of various rechargeable chemistries that either suffer loss of capacity from excess discharge (Pb Acid, NiCd, NiMH, etc.) or have the potential to fail horribly (lithium chemistries).
Lithium AAs, while they exist, are fairly rare and not the same chemistry as the rechargables. As far as I know, there's no danger in taking them all the way to dead either.
I have a number of wireless devices ( remote thermometers, rain gauges, etc ) that use AA and AAA cells and I have tracked the failure voltage of most of them for several years. I fresh cell will be a bit over 1.5 volts and good design SHOULD permit operation down to about 1 volt per cell. However, virtually all of the devices I have quit working when the cell voltage gets below about 1.34 volts. The devices use between 2 and 4 cells each, and I have to change batteries in most of them between one and two times per year. I AM an engineer and understand that "there ain't no such thing as a free lunch" but most of the devices are low average current drain with intermittent higher current peaks (a sensor that transmits a new reading every couple of minutes). A device like this, with an appropriate capacitor for peak current (which most of the devices already have internally), would cut down the number of batteries I use per year significantly. For the price mentioned in the article I will buy a few sets of these as soon as they hit the market.
And there's math behind it, too. To raise the volts, you have to lower the amps. It'll work until it can't provide enough current for the device that it's powering. The form factor is the tricky part, because you need to fit a boost coil and a capacitor in there somehow, and they might have to custom-wind the coil to make it fit, making it more costly to manufacture than it would be with off-the-shelf parts.
It would also have to know when the device is turned off. I think the Joule Thief design puts its power switch before the boost converter. You can't do that when wrapped around a single cell.
Another "too good too be true" is if you have a "pipe"-style battery compartment and the batteries leak, it could be harder to extract them. Tray-style battery compartments should be no problem.
But if they really work like they ought to work, I want some. Even if it's only a 2x lifetime, I want to use them in an IR remote control. One big problem with IR remotes is as the batteries get weaker, contact resistance becomes a problem. You can make batteries last longer by rotating them in place a little, which I guess cleans the contacts a tiny bit. Just boosting the voltage should help things right there.
#naabhaprzrag, #sverubfr-000, #agi-fcbafberq, negvpyr[pynff*=' negvpyr-ary-'] { qvfcynl: abar !vzcbegnag; }
Leaks and corrosion isn't "fail catastrophically", and typically happens after the battery has been dead for some time and the seals fail. Taking them to zero wasn't the problem - not removing them after they were dead was where the problems started. Many rechargable lithium chemistries, however, will generate oxygen and/or pure metal in bad places if excessively discharged (or charged), which then can translate into burning and toxic gases. Now that's catastrophic.
Because the device can't tell whether you're using an alkaline battery or not, and if you run a rechargeable battery down to an alkaline battery's minimal voltage, you'll permanently damage the battery.
Check out my sci-fi/humor trilogy at PatriotsBooks.
The deceit is obvious if you look at the discharge curve.
Yes, if you throw it away at 1.4V under load, most of the capacity remains. But it is bullshit because nobody does that.
High-drain devices will cope with much lower voltage, and low drain devices (like remote controls) will almost completely deplete the battery before you notice a drop in effectiveness.
For real high-drain devices like cameras, most people use NiMH, which has a nominal 1.2V only.
The boost converter will run as low as 0.6v. That IS an improvement, since most devices DO power down at 1.0v. But I also call hogwash on the "no extra risk of leakage". Alkaline cells use an inner layer of the case as the cathode. This inner case is invariable damaged by discharge. The deeper the discharge, the more severe the damage. Most reasonably modern C/Zn and AM cells have a second can outside of the first one to reduce the risk of leaks. But the battery may still fail and leak, and the fact that you have a weak battery in your device for longer RAISES your risk of a leak.
Plus, more hogwash. The "voltage drop slows at lower voltage levels". Alkaline batteries really do have a fairly linear discharge curve for SoC. The dubious claim that it slows is assuming a continuous resistive load, which by Ohm's law says that power will drop 4x for each 2x drop in voltage.
Not to say these boosters aren't useless. If your device shuts down at 1.3v (not unreasonable for older generation digital devices), you can use that battery for a lot longer. And where these things really come into their own is on rechargeables that OCV at a lower voltage that may fail to drive certain devices.
There IS a caveat though. A very, serious, caveat.
You lose ALL SoC INFORMATION IN THE BATTERY.
When you connect a booster, you forfeit all advance warning that your battery is low. You're at 1.5v until you aren't and you're high and dry.
And of course battery companies are going to be thinking of chemistry. Because implanting a $10 booster into every $1 AA alkaline battery is going to make these cells prohibitively expensive.
It's definitely a cool device, but it's not worth the hype this author is giving it.
Critical warning. This is an active circuit you're placing on your battery. Alkalines have always shined in very low current applications. Attaching an active converter circuit will put a continuous (though light) load on the battery, slashing its shelf- and very-light-duty life.
Over the span of 60 hours in a Game Boy, it's not much. But over the span of a year or two in a desk clock, it becomes significant.
Potentially significant enough to fully offset and even overcome the "unlocked" power now available to you by using it at the lower voltage.
Depending on what you're doing with your battery, you could see -50% through +300% lifespan. Degradations are for microamp-scale super long life devices, where the load of running the Batteriser forms a significant fraction of the running power. Biggest boosts are for devices that shut down at abnormally high voltages.
Still waiting on Serviscope_minor to wake up to fucking reality and realize that Jessica Price isn't going to fuck him.
The problem is that many devices require ridiculously high minimum threshold voltages just to work.
TI, for example, sells a remote control IR encoder that requires a supply voltage of 2.7V. That means two AA batteries in series run down to below 1.35V apiece will not run a device with that IR encoder.
A typical AA battery will deliver only about 0.40 AH before it runs down to 1.35V. That 0.40 AH is of a 2.1 AH total. That's a huge waste.
If it holds a constant 1.5V output the current draw from the device will also remain constant. What *will* happens is that as the battery terminal voltage (input to the boost converter) drops, the current drawn from the battery will go up, not down. It effectively turns the load into a constant power device.
I am skeptical about the life-saving claims. Alkaline battery-power devices are typically expected to operate down to about 1V terminal voltage. Since the primary effect of discharging is ion depletion, the internal resistance of the battery is what is changing, meaning by the time you get to doubling the current at low states of charge, you will be depleting it much faster. So the time of use will fall off a cliff very abruptly at the end.
I get a bit more mileage out of batteries by starting them off in a higher demand item (like an XBox controller) and when the battery is no longer powerful enough for that, I put it in a bin to be used for TV remotes.