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**rickst29** · 03-25-2020, 10:42 AM

The BMS 'over volt disconnect' charging limit is 14.6V, a low figure which is becoming more prevalent in new Chinese LiFePO4 batteries. It makes charging a bit more gentle.

But IIRC, the Progressive Dynamics Lithium chargers (including my 'Wildkat') will run "Constant Voltage" at 14.7, which is too much for completing the battery charge at 100% of capacity. These batteries will pull the entire output of a Converter until they are nearly done, so a "Constant Current" limit occurs first (at a slightly lower Voltage). But when battery charging voltage begins to rise, in the last 5-10% of charge capacity, the BMS might disconnect a tiny bit earlier than you like.

OTOH: I have complained, previously, that the PD "Lithium" Converters will try to keep the battery nearly 100% charged. While good for Lead-Acid, that's not an optimal SOC for Lithium lifespan. With BMS cutting of the charger at high voltage, my complaint goes away, and the batteries will last longer.

Edit 2020-06-12: The PD does not tend to leave the battery overcharged. Not a problem!

03-25-2020, 10:42 AM	#30
rickst29 yes, they hunt lions. Join Date: Aug 2005 Location: Reno, NV Posts: 1,318	I have just one minor concern with this battery - and other recent Chinese models. The BMS 'over volt disconnect' charging limit is 14.6V, a low figure which is becoming more prevalent in new Chinese LiFePO4 batteries. It makes charging a bit more gentle. But IIRC, the Progressive Dynamics Lithium chargers (including my 'Wildkat') will run "Constant Voltage" at 14.7, which is too much for completing the battery charge at 100% of capacity. These batteries will pull the entire output of a Converter until they are nearly done, so a "Constant Current" limit occurs first (at a slightly lower Voltage). But when battery charging voltage begins to rise, in the last 5-10% of charge capacity, the BMS might disconnect a tiny bit earlier than you like. OTOH: I have complained, previously, that the PD "Lithium" Converters will try to keep the battery nearly 100% charged. While good for Lead-Acid, that's not an optimal SOC for Lithium lifespan. With BMS cutting of the charger at high voltage, my complaint goes away, and the batteries will last longer. Edit 2020-06-12: The PD does not tend to leave the battery overcharged. Not a problem! __________________ TM='06 2619 w/5K axle, 15" Maxxis "E" tires. Plumbing protector. 630 watts solar. 450AH LiFePO4 batteries, 3500 watt inverter. CR-1110 E-F/S fridge (compressor). TV = 2007 4runner sport, with a 36 volt "power boost".