5. Lead-acid battery market

5.1 Batteries for internal combustion vehicles

As we've seen, they're usually referred to as "SLI batteries". When the internal combustion engine is stationary, the battery supplies various auxiliaries (lighting, alarm, door locks, etc.), but its essential role is to start the engine. When the engine is running, the battery is buffered by an alternator-rectifier system, powerful enough to supply the electrical energy required by the vehicle. Consequently, the battery is designed to supply the intense (some 100 A, i.e. of the order of 5 C) and brief (a few seconds) currents required to start the engine. In the event of difficulties, the battery is discharged in a few minutes, but the discharge is not very deep. Except in the event of an incident, the battery is in quasi-floating mode....