Multiple Li-On charger. Is this possible?

[Lucacri]

Hi guys,

I have several 14500 laying around but I find myself always rotating the same 2 sets of batteries. Basically, I take away the 2 used batteries and swap them with the charged ones. I guess, in the long run, this leads to have 4 batteries with lower capacity and a bunch of new batteries still wrapped

So, while I was taking a nap (yes, I think about the e-cig while I sleep), I came up with an idea:

make a rig that accepts few batteries and charges them all in once. Ideally, the rig would be like a "water-slide": put the used bats on the top, get the freshly recharged ones on the bottom.


I have a future as industrial designer


Questions:
Could I use the AC charger safely to charge several batteries (probably slower, but it should do the trick)?
Any idea/improvement?

 

[duby]

First, generally speaking you don't want to leave li-ion batteries on a charger for more than 8 hours.
Many cheap chargers never actually cease charging. So you can over charge and cause the batteries to explode. Protection circuits in batteries help with this by cutting off the current when the battery reaches a threshold.

Charging batteries in parallel works, but some issues can arise. If the batteries are all at varying states of charge the current division can muck up the chargers ability to know when to shut off. Yet again causing your batteries to be over charged.

A Balance charger could easily handle multiple batteries, but it would require them being charged in series. Since by its nature the batteries are charged and monitored individually you'll have better luck with rate of charge and little chance of overcharge.

Any idea/improvement?

Get a second charger and label your batteries. What happens if your current charger dies? Its always good to have a back up regardless.