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As much as I like Dave Jones, I think he's concentrating on the wrong bits here. The idea is completely bad. Sorry. It's a pile of crap. It shouldn't be on the

As much as I like Dave Jones, I think he's concentrating on the wrong bits here. The idea is completely bad. Sorry. It's a pile of crap. It shouldn't be on the market. Sure you can build a boost converter that gives you a constant 1.5v. That's not a bad idea. I've actually designed a couple of these myself on a larger scale over the years (professionally, for military radio equipment, not Joule Thief hacks). That's not under debate. The following points are: 1. Even the best alkaline batteries leak if you discharge them too much so you'll end up destroying your equipment and the Batterisers that you invested in at the same time. Seriously, take a 220 ohm resistor and stick it across a Duracell AA battery and leave it for a few days. You will come back to a rancid mess. 2. There is a cost. So you're going to need 4 of these for your average device that requires a 6v supply. now my 12v radio packs are 8xAA batteries so imagine the incidental cost over the top of the batteries there. To power kids toys you could have tens of these in the house. Over the top of disposable batteries, it's a poor investment. 3. 8x is simply horse shit, as DLJ points out. Even with a fairly efficient conversion ratio, and I haven't done the figures, just a finger in the air estimate based on the amount of energy your average alkaline AA has, you're looking at 1.2-2.0x the life. 4. Wonderful things like AA batteries are terribly variable in the tail end of their discharge curve. Not all batteries in a pack are going to still be kicking out current or even have a suitably low internal resistance compared to their immediate colleagues. If one of these fails early, it will take the advantage away from the rest of the cells instantly. 5. Noise. Boost converters usually generate a lot of electrical noise in the signal paths. If you have any analogue parts, particularly audio that are expecting to have a relatively noiseless power supply (batteries are quite noise free) then the design will perform worse with these. Now the killers: 1. If this was such a great idea, why is it not built into the equipment? (because it represents a risk to the equipment) 2. Why the hell would you bother with this when Sanyo (well Panasonic now) Eneloops represent a better investment than both alkaline batteries and these. They handle over 1000 charge, discharge cycles no problems at all, have a good very good shelf life due to low self-discharge characteristics, don't leak and have a decent peak current capacity and discharge curve. It's just a waste of time.

minthd 11y ago
Good post. But why 1000 charges is useful for most home equipment where batteries last a relatively long time ?
- wumbernang 11y ago
  Only because they are then fungible. Once you dispose of that calculator that takes 4xAA batteries and lasts 6 months, you can whack the cells in a Furby's butt and charge them up once a week until your children get rid of the damn things :-)
- outsidetheparty 11y ago
  You, sir, are quite clearly not the parent of a pre-teen child We go through packs of AAs like popcorn around here
- bitwize 11y ago
  Two words: Wii Remote.
mindslight 11y ago
> 1. If this was such a great idea, why is it not built into the equipment? (because it represents a risk to the equipment) Because pennies add up when making millions of units, and the TCO including batteries isn't a point of competition. Still, it would obviously be more efficient to run a larger boost converter on 4 cells in series rather than multiple tiny energy-harvesting ones. I've also got to wonder about the standby power of this device. IR remotes are on very little and last for years with the right battery, so any additional draw is going to greatly reduce their lives. And like you said, high draw devices are changed regularly so recharageables make more sense. IMHO products like this aren't really about the tech and appeal to a large audience for their simplicity, not their efficacy.

minthd 11y ago

Good post. But why 1000 charges is useful for most home equipment where batteries last a relatively long time ?

wumbernang 11y ago
Only because they are then fungible. Once you dispose of that calculator that takes 4xAA batteries and lasts 6 months, you can whack the cells in a Furby's butt and charge them up once a week until your children get rid of the damn things :-)
outsidetheparty 11y ago
You, sir, are quite clearly not the parent of a pre-teen child We go through packs of AAs like popcorn around here
bitwize 11y ago
Two words: Wii Remote.

mindslight 11y ago

> 1. If this was such a great idea, why is it not built into the equipment? (because it represents a risk to the equipment) Because pennies add up when making millions of units, and the TCO including batteries isn't a point of competition. Still, it would obviously be more efficient to run a larger boost converter on 4 cells in series rather than multiple tiny energy-harvesting ones. I've also got to wonder about the standby power of this device. IR remotes are on very little and last for years with the right battery, so any additional draw is going to greatly reduce their lives. And like you said, high draw devices are changed regularly so recharageables make more sense. IMHO products like this aren't really about the tech and appeal to a large audience for their simplicity, not their efficacy.