batterynoob could use some help ;)

[epoxy]

hello all,

the reason that i joined this forum today is my search for
a nice charger that will charge NimH 1/4AAA cell's.
like the GP11AAAm

http://www.gpbatteries.de/HTML/pic/GP11AAAM REV.2(TRS0239).PDF

or better said, a "pack" 2 of them. with a staggering 2.4V :candle:
(or just about)

yeah, these are realy small ( and hard to get btw) and use very low (dis)charge currents.
my trouble is finding a affordable charger that could charge at low mA.
most of them only do 100mA or 200mA.
100mA does work, but...
something more controlable in the low range, like maybe steps of 50mA or 25mA would be more suitable.?:thinking:

as i'm totaly new to this charging thing, i really could use some advice.

thanks !!

 

[Fallingwater]

If you can find one that charges at a proven 100ma then it's ok. That PDF clearly states a "fast" charge of 110ma is acceptable.

Problem is, most chargers that let you set the charging current in small steps are professional RC-grade ones, and they are not cheap.

I've been charging a 100mah 1/4AAA (out of a tiny RC truck) myself using my Hyperion 5i charger (RC-grade, expensive). The lowest charge current the 5i can charge NiMH at is 100ma, and the cell seems quite happy with it.

If you don't want to splash out on a RC-grade charger you could use a cheap "dumb" charger meant for charging NiMH AAs and AAAs.
You need to measure the charging current with a multimeter, of course, and then carefully time the charge yourself. What is trickle charge for an AA is likely to be full blast fast charge for a tiny 1/4AAA, so you don't want to leave it in for too long.

 

[epoxy]

hee, great advice, thanks :twothumbs

tiny RC truck ? sounds great :thumbsup: mine are in a tiny RC tank :naughty:

and yes, there are very nice almost professional chargers on the marked,
but i was looking for a solution under €200 :sigh:
most of the more regular chargers i find do have 100mA or so
as the lowest setting.
and indeed it should be ok for a quickcharge.

but i was just wondering if there was a nice cheap solution to my problem.
come to think of it, the 1/4AAA is not a very common type of battery,
so to make special chargers for a battery almost nobody uses doesn't make a whole lot of sense.

cheers :thumbsup:

 

[Fallingwater]

and yes, there are very nice almost professional chargers on the marked,
but i was looking for a solution under €200

You have to go really pro to spend more than €200. My Hyperion 5i AC/DC cost me €110, and if you don't need AC input (if you have a grunty enough 12v power supply and/or a lead-acid battery or two sitting around) you can get the ordinary 12v-powered Hyperion 5i (non AC/DC) for considerably less.

Last I checked the standard 5i doesn't have a program for charging LiFePO4. You can charge them on the AC/DC with the A123 setting.

but i was just wondering if there was a nice cheap solution to my problem

Dumb charger, multimeter, stopwatch.

 

[epoxy]

lol, thanks fallingwater, but i wasn't looking to go that cheap.

your hyperion looks a lot like jamara Xpeak 3+ I was thinking of buying.
http://www.lipopower.de/shop/pages-...ra-jamara-x-peak-3-plus-max-5a-1-5-lipos.html

maybe it's the same charger, with a different jacket ?
it is listed as having steps of 50mA (charge) and 10mA (discharge)
but i don't know if this is correct.

and for less than €60,-

still, it doesn't (dis)charge under 100mA unfortunatly .
but this could be the one i'm looking for. :thinking:

 

[Fallingwater]

still, it doesn't (dis)charge under 100mA unfortunatly .
but this could be the one i'm looking for

It seems to me it can discharge at up to one amp.