Lithium Battery Nomenclature

Lithium Battery Nomenclature


Loss of capacity due, for example, to loss of lithium ions or spallation of anodes. This may be due to use (charging and discharging) and/or open circuit rest (calendar aging)


The positive electrode. In lithium-ion batteries, these are most often small particles of graphite.


The complete energy storage unit consisting of several modules


The amount of charge stored in a battery or cell, usually specified in ampere-hours (Ah). 1 A h = 3600 Coulombs (C)


The negative electrode. These typically include lithium transition metal oxides: for example, lithium nickel manganese cobalt oxide (LiNi 0 33 Mn 0 33 Co 0 33 O 2 )


The smallest unit of a battery


In electrochemistry, this term can designate either the inorganic salt (ex: LiPF 6) or the salt + organic solvent

End of Life (EoL)

The point at which a battery becomes unsuitable for its current application. For automotive batteries, this is typically 75-80% health


The energy stored in a battery is specified in Watthours (Wh) or kiloWatthours (kWh): 1 Wh = 1 Amp Volt x 3600 s = 3600 AVs = 3600 Joules

Energy density

Energy per unit volume (litre) of the battery

Galvanic battery

Usually just called a cell. A device which, when charged with electricity, is in a higher state of energy than when discharged. Upon discharge, the stored chemical energy is released as an electric current

OCL cathode

Lithium cobalt oxide, LiCoO 2

LFP cathode

Lithium iron (ferrous) phosphate, LiFePO 4

Cathode LMO

Lithium manganese oxide, e.g. LiMn 2 O 4


Manufacturer-specific term, e.g. set of cells arranged in series and/or in parallel

Cathode NEC

(lithium) Nickel Cobalt Aluminum oxide, e.g. LiNi 0 8 Co 0 15 Al 0 05 O 2

NMC cathode

(lithium) Nickel Manganese Cobalt oxide, e.g. LiNi 0.33 Mn 0.33 Co 0.33 O 2 (NMC 111), LiNi 0 6 Mn 0 2 Co 0 2 O 2 (NMC 622)

Open circuit

The state when a battery or cell is disconnected from an external circuit

Open Circuit Voltage (OCV)

The difference in potential (voltage) across a cell or battery when no current is allowed to flow. This can be correlated with the state of charge (SoC)


The inorganic compound used to produce ions in the cell. It is typically lithium hexafluorophosphate (LiPF 6 ) which dissociates in the organic solvent to produce lithium cations (positively charged ions, Li + ) and hexafluorophosphate anions (negatively charged ions, PF 6 – )


A plastic film permeable to lithium ions and hexafluorophosphate which prevents the anode and cathode from touching and causing a short circuit

Solid Electrolyte Interface (SEI)

The protective layer that forms on the anode during the first charge from the reduction of LiPF 6 and solvent which prevents further explosive electrolyte degradation and thermal runaway


Mixture of organic carbonates, containing ethylene carbonate, as it is essential for the formation of SEI. Ethylene carbonate is a solid at room temperature and other carbonates are essential to reduce viscosity

Specific energy

Energy per kg of battery

State of Charge (SoC)

The amount of charge stored compared to that equivalent to a full charge, expressed in %

State of Health (SoH)

The amount of charge currently stored when fully charged compared to that stored (when fully charged) at the start of the cell or battery life, expressed as a %

Scroll to Top