Charging rechargable cells - 3 into 4 don't go

[Whiskers]

Lots of gizmos use 3 AA or AAA cells yet the wart chargers only seem to charge in pairs (are they in series?) Is it safe / wise to use a charged cell of the same capacity to make up the pair in the hope that the charges will balance. This has to be everyone proof, I am trying to keep different sets of batteries together as there are many different brands and characteristics.

[richardash1981]

Lots of gizmos use 3 AA or AAA cells yet the wart chargers only seem to charge in pairs (are they in series?) Is it safe / wise to use a charged cell of the same capacity to make up the pair in the hope that the charges will balance. This has to be everyone proof, I am trying to keep different sets of batteries together as there are many different brands and characteristics.

 

The wart chargers do often charge in series (the cheap ones), and so can't charge a single cell on it's own.Putting a full one in might get it to charge but won't be good for the cells (either of them) in the long run, because you will be over-charging one of the pair, and probably fail to fully charge the other one, which will then be the most discharged which runs flat first. The same will apply to the used pair in time, as the cells age and their capacities diverge.

Ultimately, series pair chargers are not a great idea, but separate cell chargers are easily available, albeit more expensive and usually in a desktop rather than wall-wart form factor.

[dmxlights]

With using rechargable batteries in radio mics and body packs, we found some of the battery chargers that charged batteries in pairs did not charge right so we got some chargers that charged one cell on its own and we got better results with them.

here is a link to one we use

https://www.ebay.co.uk/itm/Japcell-BC1600-battery-charger-16-slots-for-AA-AAA-NiMH-rechargeable-batteries/162089524461?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m1438.l2649

 

[adam2]

I agree that any improvised way of trying to get THREE charged cells by using a charger that only charges in pairs is doomed to failure.

 

Sooner or later some cells will be charged twice, or different types will be discharged in series, or charged and not charged cells be used in series. Simply buy a charger that handles three cells, or preferably multiples of three at the same time. I am not familiar with the product to in an earlier post, but it looks good.

 

 

 

[sandall]

Below the one dmxlights linked to are a number of sub-£7 1-4-cell "intelligent"?? chargers - at least 2 sellers claim to have UK stock. Just ordered one for the garden lights strings, as by now they will all have different states of charge.

[d_korman]

Here you go...

 

https://www.amazon.co.uk/ANSMANN-Powerline-discharge-rechargeable-batteries/dp/B00A76B18W

 

Charges up to 4 independently. I've had one (earlier version) for years.

Edited March 26, 2020 by d_korman