Mixing battery Amp hrs

tonyc07

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I have 2 x 135 Ahr batteries (wet) for my on-board services.

Thinking of increasing the total size of this bank. So....

Can you mix dissimilar AMPhr's? For example could I add 2 x 150 Ahr batteries to the bank? Or, Alternatively add 2 x 110 AMPhr batteries?

Cheers,
 
Yes as asj1 says but by different types it's principally gel type with others. Not sure if AGM (which may be what he meant by sealed) can be mixed with ordinary flooded acid batteries, I thought they could. More informed advice required.

BUT you are talking about a lot of battery capacity. I assume you have so much on board electrical gear that you have determined that you need that much but do you have the generating capacity to charge it all. Being unable to charge them fully and therefore leaving them only partly charged will shorten their lives no end
 
Thanks for the advice and info.

I'm thinking of fitting an inverter to run most of the kids & SWIMBO's kit. I also do have 2 x plotters so would feel a little more comfortable on those longer extended cruises.

One further question......If there are differing size (AMPhr) batteries in the bank - how does the charger know when each is charged? Will it only charge to the lowest capacity and leave the bigger undercharged; or continue charging and over cook the smaller?

Regards,
 
[ QUOTE ]
One further question

[/ QUOTE ] It will charge them all to the same %age of fully charged. That is if you charge until one is ¾ charged the other will be too ,regardless of their capacities.

Don't forget you can't charge them by running the battery charger off the inverter /forums/images/graemlins/grin.gif
 
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