Print

Please login or register.
1 Hour 1 Day 1 Week 1 Month Forever
Login with username, password and session length.

[Tralee]

I currently use 4 6volt 4.5amp lead acid batteries, anyone know of a battery charger that will charge the 4 batteries at the same time?

[justboatonic]

Any SLA battery charger for model usage ie something like an MFA 2v, 6v, 12v charger, will do. Just connect your batteries in series. Yes it will take longer to charger ie roughly 4 times as long as it would take the same charger to charge one SLA.

I sometimes do this with my BMI NiMH charger and 2 packs of 3700 cells.

[Tralee]

Thanks for the help will try this

[Aage]

4 batteries, each at 6 volt can hardly be charged when hooked up in series. First of all you would need a 24 volt charger (for lead acid you will actually need about 34 volts) . I suggest that the batteries are charged in parallell using a 6 volt charger. Besides that - charging a multiple of batteries isn't that easy and I suggest to charge max. 2 at a time - in parallell. If you charge "in series" the time taken will be the same as long as the charger has the same charging current at 6 V as at 24V (often the case). Since batteries are detoriated differently (especially lead acid batteries) I still suggest that the best way of charging a lead acid battery is one at a time.

Aage

[malcolmfrary]

If you lack experience, charging one at a time is simplest and safest. 
But.... two 6v batteries connected in series gives a 12 volt 4.5AH battery.  A SLA charger set for 12 volts will not know the difference, and will charge them accordingly, in the same length of time that it took to charge one 6 volt.  The other pair could be treated similarly.  If this was connected in parallel with the first two, you would have a 12 volt 9 amp-hour battery. 
As AAGE says, this depends on the batteries all being in a similar state of charge or discharge, and being in similar condition regarding their ability to be charged. 
If there are dissimilarities between elements in a series chain, then uneven charging may result, meaming that the "better" cells will be overcharged, and probably become as bad as the others.
In a parallel network, on connection, they will do their best to even out the voltage between themselves.  This can result in massive circulating currents.  Because of the construction of lead acid cells, this can in extreme case cause local heating which causes the plates to warp.