Posted: Fri Jan 14, 2011 4:27 pm
I have just bought a Kewet Buddy EV which is v low miles but has been standing uncharged
I now have the batteries on a long slow trickle charge, to de-sulphate etc.
Can anyone give definitive technique for this?
Re: Battery recharging
Posted: Sat Jan 15, 2011 10:14 am
Sadly not, some people suggest these pulse chargers or dopes that can be added to the batteries, but personally I've not found anything better than a very long and very slow charge to recover them ....... if they will.
It all depends on the condition and type of the batteries when they were allowed to get into this state, IF they where fairly good and have not done much work and the reason the vehicle has been left un-charged is due to some other failure then the chances are they will recover to a degree BUT it will take a long time and when I say a long time, I've found it takes several months on a very slow charge, keeping an eye on the terminal voltage so it doesnt start boiling cells that become fuily charged before others.
IF the batteries have already done 1/2 of their life or more then the chances of recovery to any reasonable degree becomes a lot harder and even if they do recover the efficiencies are very low on these batteries
Hope that helps ??
Re: Battery recharging
Posted: Sat Jan 15, 2011 11:23 am
Would it help to relate a fortunate experience?
Some years ago another BVS member gave me some (65a/h?) Optima Yellow Top AGM lead-acid batteries
They were well-used, remaining life unknown, so he suggested a low-cost idea worth trying
This was a 240v. input, 13.8v.dc output, stable-voltage supply unit often used in audio
I bought one for £20-ish IIRC, linked it to all the YTs in parallel, with a suitable fuse in each line, as he advised
Time passed, (more than a year, by the time I got round to trying the results)
I don't know how good a new YT is, but these "old" batteries gave me great service for several uses
The best 4 went into a home-converted Hodna Helix scooter with a 48v ETEK
(this carried me AND the Mrs on one memorable short trip)
Others were used as temporary substitutes in i.c machines, and for emergency-start 12v.dc sources
It seems to me the long, slow, trickle-charge effect may have helped
The above is definitely very subjective, and fortunate, but maybe worth a try on the "Buddy"?
All the best