Sodium-ion battery glossary
Anode
- The electrode that stores sodium during charging in a sodium-ion cell; commonly hard carbon.
BMS
- Battery-management system: electronics that monitor and protect cells.
Cathode
- The sodium-containing positive electrode when the cell is discharged.
Cycle
- Energy throughput equivalent to one full charge and discharge, often accumulated from partial use.
Energy density
- Stored energy per unit mass (Wh/kg) or volume (Wh/L).
Hard carbon
- A disordered carbon widely used as a sodium-ion anode.
LFP
- Lithium iron phosphate, the main lithium-ion competitor for stationary storage.
NMC
- Nickel manganese cobalt lithium-ion chemistry, valued for high energy density.
Round-trip efficiency
- Energy returned divided by energy put into a battery system.
State of charge
- An estimate of remaining usable capacity, expressed as a percentage.
Thermal runaway
- Self-accelerating heat generation that can lead to venting, fire or propagation.
Usable capacity
- The energy a system permits between its operating limits, which may be less than nominal capacity.