1. Electrical contexts and storage requirements

1.1 Current uses of electrical storage media

The most familiar electricity storage needs are for portable electrical (tools) and electronic (telephones, microcomputers, etc.) applications, for which it is acceptable to pay a high price for on-board kWh in view of the service provided (portability). For these small electrochemical batteries, it appears that the investment cost is between 2 and 10 e/Wh of capacity. For this investment cost, we can associate a simplified cost of use representing the cost of the Wh exchanged with the storage system. This corresponds to the ratio of the investment cost to the total quantity of energy that can be exchanged over its lifetime. The latter is the product of the energy capacity and the maximum permissible number of complete charge/discharge...