SparkFun Forums

[jandirks]

I found this and would like to hear your opinions on it:
http://www.i-hacked.com/content/view/207/44/

Does this really work or is it another hoax.

Thank!

JD

[leon_heller]

Alkaline batteries can be recharged, I used to do it. It's OK where the current drain is limited.

Leon

[Kuroi Kenjin]

Techincally you should be able to reverse any chemical reaction. It just depends how much energy you need to throw at it. I don't believe, alkaline's aren't the most efficient in terms of recharge. Recharging is still better than throwing them out in my opinion.

One thing that would be a good idea on that recharger would be also limiting by temerature. 24 ohm PTC termistor in stead of a straight resistor with mounting near the battery would make it a little safer on the initial charging of weak batteries (since this is a regulated current source now).

I also don't think charging batteries in series is a good idea either, since you don't know the distribution of charging. Parallel with some diodes would work the best. As well as having an input voltage of around 1.5V + the average voltage drop of the circuit so that the current would be reduced to 0 on a full charge.

[wiml]

For a while you could buy "rechargeable alkalines", but I haven't seen them in a while. I have heard that normal alkalines can be recharged to some extent, but I don't remember what the downside is. They might not last very many cycles, or something like that.

[leon_heller]

For a while you could buy "rechargeable alkalines", but I haven't seen them in a while. I have heard that normal alkalines can be recharged to some extent, but I don't remember what the downside is. They might not last very many cycles, or something like that.

I tried them and they didn't seem any better than ordinary alkaline cells in the supplied charger. That's probably why they aren't around any more.

'Dirty' DC - unsmoothed rectified AC - is supposed to be best for recharging. The technique has been around for over 40 years.

Leon