Lithium Iron Phosphate Battery Question

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AllPawDrive
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Lithium Iron Phosphate Battery Question

Post by AllPawDrive » Wed Jul 29, 2020 12:23 pm

Question with regard to Lithium Iron Phosphate Batteries:

If the batteries were regularly charged at the optimal voltage, but the charging current was regularly lower than the manufacturer’s optimal bulk current rate...say 25% lower.

Would there be any impact on the lifespan of the batteries?

If there is an impact, would adding a generator charge periodically at the ideal charge voltage and charge current minimize potential negative impacts on lifespan?

Thanks,

Dave

raysun
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Re: Lithium Iron Phosphate Battery Question

Post by raysun » Wed Jul 29, 2020 12:38 pm

AllPawDrive wrote:
Wed Jul 29, 2020 12:23 pm
Question with regard to Lithium Iron Phosphate Batteries:

If the batteries were regularly charged at the optimal voltage, but the charging current was regularly lower than the manufacturer’s optimal bulk current rate...say 25% lower.

Would there be any impact on the lifespan of the batteries?

If there is an impact, would adding a generator charge periodically at the ideal charge voltage and charge current minimize potential negative impacts on lifespan?

Thanks,

Dave
Most vendors make noise about charging at their specified rate, but LiFePO4 doesn't really charge like lead acid, one is not executing a chemical reaction,one is simply pushing ions from one node to the other. The mark of complete ion-pushing would seem to be cell voltage, so if that target is being hit, charging should be complete.

It won't hurt to charge at the recommended rate periodically, but again, it's not like lead acid Equalization charging. If the battery design employs top-balancing, then the BMS is likely handling that transparently.

You might check with the manufacturer for confirmation of the above.

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