On Sun, 3 Apr 2016 11:18:14 +0100, polygonum
wrote:

On 01/04/2016 17:00, wrote:
I have lots of AAA and AA NiMh batteries which have been through quite
a lot of discharge/recharge cycles. I have a tester which tells me if
they're charged or not but I'd really like to check their actual
capacity. Some of the AAA ones at least have very little capacity now
but it's difficult to check.

I could rig up a simple resistor discharge with some sort of computer
monitoring via an AtoD interface but surely someone out there must
produce and sell such a thing for not very much.

Has anyone come across anything like this?

How I wish someone would come up with a charger that had extendible
bays. By which I mean you could add on any number of very simple cell
holders. The charger would look at the first set of cells, do whatever
and go on to the next set.

It would have to have connections to each of the cells (as the better
fixed bay chargers generally do) and I'm not sure if that would then
bring in it's own issues (voltage drops over the leads affecting
accurate voltage detection)?

That would allow you to have all your rechargeable cells nicely stored
and kept at whatever charge level, discharge cycling rate, etc. you
might want. Might need some way of indicating which cells are being
processed right now, etc., but surely nothing particularly clever.

There is no reason you couldn't 'cycle' a basic / lower rate charger
over various sets of cell-packs, as long as they were all the same
type etc (chemicals and capacity).

Sure it would still only charge up to four at a time - but that is
enough for many of us!

I love my Ansmann Energy 16 because not only does it handle up to 16
cells / batteries at once (12 x AA/AAA (or 6 x C/D) + 4 x PP3) it
charges them slowly and individually. There is nothing more rewarding
than buying a set of 12 new AA's, putting them in the charger and
seeing them all indicate 'charged' at similar times. Take an old batch
of 12 that are supposed to be the same and you would be surprised how
much difference there can be in the finished times.

Put the quickest cells in the BC 700 and that generally confirms
under (marked) capacity.

On the subject of charging multiple targets, I built a 12V charger /
switcher designed to maintain up to 4 x 12V Lead acid batteries as
typically found on 4 motorcycles. Some of these intelligent chargers
(line the Opitmate series) ...

http://accumate.co.uk/optimate%206.htm

.... can be quite expensive and so it would be quite costly to have 4
off to cover 4 bikes. So this solution switches the charger around as
many of the 4 outlets have batteries on the end (so you don't waste a
'slot' when a bike is disconnected) and you can set what period it
stays on each (6 - 48 hours or so).

Cheers, T i m