Topic: Which battery charger?

[danny7147]

Right guys, got a predicament. At a show a couple of months ago a really nice woman gave me two wheelchair batteries. They work brilliantly, small and powerful, but they now need charging and I'm stuck on finding a suitable charger! They're valve regulated lead acid 36ah, and it says that charging voltage must be around 15v with a 0.3 capacity current which not only doesn't mean much to me but also strikes me as a very tiny charger! I called Maplins and they don't sell anything suitable, trickle chargers are all too powerful, so can anyone think of a solution or find one that I can use? Would be hugely appreciated :-)

[PLOD11]

This might do it ..
www.ebay.co.uk/itm/200824445607?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649

User manual
http://www.minicars.se/service/manualer/ovrigt/imax/IMAX-B8.pdf

[gertk]

This might do it ..
www.ebay.co.uk/itm/200824445607?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649

User manual
http://www.minicars.se/service/manualer/ovrigt/imax/IMAX-B8.pdf

That is not a lead-acid battery charger..

I use something like this:

http://www.pixmania.ie/ie/uk/11820454/art/noname/hq-7-stage-automatic-12-v.html

They come in various capacities, I opted for the (slow) 5 Amp version for my 55 Ah battery and it works really well.
With 0.3 times 36 Ah (=12) you can use the 10 Amp version and charge your battery in less than 4 hours.
The charger analyses and charges the battery fully automatic.

[PLOD11]

It has a "PB" setting (2-36) volts which is "lead acid"  ...

John-PLOD11

[danny7147]

Gert, that's fantastic! When I called up a local electronics shop they said that it must mean 0.3A, and I thought 'Wow that'll take a long time to charge!', but I completely see your point that 0.3 capacity would be a 12A current! I'm wondering if my usual charger would actually work then as it's a 12V charger with a 6A current...

[gertk]

It has a "PB" setting (2-36) volts which is "lead acid"  ...

John-PLOD11

I skimmed thorught the specs and must have missed that, but anyway, it is better to have a dedicated lead-acid charger.

[gertk]

I have read the manual again of that IMAX charger and just the sheer amount of spelling errors on the display makes me shiver :-)
Also the fact that it is not suitable for batteries which are fully charged and/or slightly discharged (like sitting idle for a few weeks for example?) and that you have to select the battery type each time you connect it makes it not so good a candidate I think. Just my 2c..

[danny7147]

Right, I bought a charger earlier, it's a smart one and adapts to different types. One thing that's puzzling me, it does gel type, but says it's not suitable for agm which, sods law, two of my three are! I've also read that agm are the most resilient type, so any ideas why it's not compatible?

[Ton C5]

It says i my charger manual that AGM battery need a higher voltage then gel  (14.7 vs 14.4) 
btw i got a CTEK mxs 5.0

[danny7147]

So in theory the worst that would happen is it wouldn't have as high a charge? I called the battery manufacturers this morning and they said they didn't understand as they act the same as gel... The interweb says that agm are prone to failure during overcharging so I'll keep a close eye on the voltage, but I think it'll be undercharged rather than over!

[Ton C5]

A to low voltage is also bad voor you agm battery, you wil get sulfar (sorry don't know if this is correct English) on the plates which wil shorten your battery life