Method for managing and diagnosing a battery

A method for managing a battery, comprising:

• discharging the battery to a full discharge level (E1) and measuring the temperature Tfindch of the battery (E2) when the full discharge level is reached;
• and
• charging the battery to a full charge level (E3) and measuring the temperature Tfinch of the battery (E4) when the full charge level is reached,
• these two steps of charging then discharging or charging then discharging being consecutive;
• and
• calculating the inaccessible charge quantity Qdch(Tfindch) at the end-of-discharge temperature Tfindch following the step of discharging to a level of full discharge of the battery, knowing the relation giving the inaccessible charge quantity Qdch(T) of the battery as a function of the temperature T, and
• calculating the maximum admissible charge quantity Qch(Tfinch) of the battery at the end-of-charge temperature Tfinch, by the relation Qch(Tfinch)=qch+Qdch(Tfindch), where qch corresponds to the quantity of charges transmitted to or released by the battery to change from a full discharge level to a full charge level or vice versa.