Lithium-ion Batteries

Lithium iron phosphate batteries can be discharged much deeper, weigh less, hold their voltage better and last for many more cycles. Lead-acid batteries cost less upfront, are well proven and easily recycled, but lose life under deep or daily cycling. The better value depends on how often you cycle the battery.

A battery management system is the electronics that monitor each cell, balance them and protect the pack from over-charge, over-discharge, over-current and temperature extremes. It also reports state of charge and alarms to the inverter or charger over a communication link. A mismatched BMS protocol is the main reason lithium packs do not work with an inverter.

Not always. The inverter or charger must support the lithium battery's voltage range and charging profile, and ideally communicate with its BMS. Some inverters have a lithium mode, others do not. Confirm compatibility before buying, as mismatch may cause shutdowns or unsafe charging. Check the inverter and battery manuals together.

Often yes. LFP packs for 48 V systems use 16 cells in series, each at 3.2 V nominal, giving 51.2 V nominal. The terminology 48 V comes from the lead-acid and telecom convention. Always check the allowed voltage window of the charger or inverter against the pack's full-charge voltage.

Calculate the energy you want to shift into the evening or night in kWh, divide by the usable depth of discharge of the battery and by the inverter efficiency, then add a margin for ageing. Check the inverter's maximum charge and discharge current. The solar calculator on this site gives a first estimate.