Battery rejuvenation???

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tomwible
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Battery rejuvenation???

What if when a 36 volt battery pack is getting old, you take and add another 12 volt battery to it. Making a 48 volt pack, but then only charge it to 36 volts to match the scooter set up. Each battery would only have to maintain 9 volts. I am thinking this might allow you to get more life out of old batteries.

Any thoughts?

-Tom

dwkennedy
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Re: Battery rejuvenation???

Won't work. With too many batteries, the charge will terminate early with very little energy injected into the batteries. Remember, lead acid batteries are basically tapped out of energy when their no-load voltage is around 10.4 V.

Usually, one battery out of three will fail first. You can extend the life of the pack by replacing that battery (ideally, with a used battery of similar remaining capacity.) A battery analyzer that discharges and measures the capacity is helpful in figuring out which battery is the culprit.

Having a new battery in series with old batteries will also lead to the pack being unbalanced (one battery will charge up before the others, charge will not terminate, that one battery will become overcharged.)

reikiman
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Re: Battery rejuvenation???

9v is hugely undercharged for a 12v SLA battery. If you have it resting at such a discharged state it damages the battery. What you're suggesting is not a good idea.

tomwible
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Last seen: 14 years 2 months ago
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Re: Battery rejuvenation???

Thanks for all the help. From the information that I gleamed from this thread, cell charging is kind of a crap shoot in series. Is it basically dependent on each cell having similar characteristics such that each cell is evenly charged? By adding another cell you would create an imbalance. Would that be true even if the cells had the same specs? (amp/hr)

-Tom

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