One new battery question

[sonofagunn]

I know it's not recommended to replace just 1 unless the others are all nearly new. I am wondering exactly why. I have read that the one new battery can be damaged during charging by reaching full voltage first and boiling off some while the others are still charging.

Is that the only way the new battery is damaged, or does an imbalance during running the cart also harm the batteries somehow?

[Sergio]

Not only the new battery reaches full charged capacity first and then starts to overcharge, but a fully charged battery has a higher internal resistance that lowers the charging current and prevents the older batteries from fully charging.

[sonofagunn]

Originally Posted by Sergio

Not only the new battery reaches full charged capacity first and then starts to overcharge, but a fully charged battery has a higher internal resistance that lowers the charging current and prevents the older batteries from fully charging.

Thanks Sergio, so that's another charging problem, but are there any drawbacks or damage from running the cart with one stronger battery? The charging problems could be worked around by having a 4-bank charger (if one has a 4 battery 12v setup) that monitors and chargers each battery individually. I realize those multi-bank chargers are lower amp usually but they also have their advantages.

[NoleFan4Ever]

If you have to replace a battery in a used pack, just try to get a good used battery and let that buy you time until you can replace the entire pack.

[Sergio]

if You have 12v batteries and a bank charger, then you are not impacted by the limitations of charging batteries in series.

Just keep in mind that the SOC of your "Series" pack is equal to the lowest SOC in any battery, meaning if one battery can only deliver 50AH, your entire pack can only deliver 50AH.

[sonofagunn]

Originally Posted by Sergio

if You have 12v batteries and a bank charger, then you are not impacted by the limitations of charging batteries in series.

Just keep in mind that the SOC of your "Series" pack is equal to the lowest SOC in any battery, meaning if one battery can only deliver 50AH, your entire pack can only deliver 50AH.

Hmm, I see. So you could avoid the charging problems but wouldn't be seeing much (if any) benefit in run time or performance from the one stronger battery.

[Vital Enterprise]

But if your charger allows you to regulate voltage &/or current and you've only got one bad battery, you'll be saving the life of the others in the set.