LiFePO4 Lithium Battery
Lead-acid batteries have historically always been present in engine starting applications, as they have very high short-circuit currents. However, they need to be concerned by the challenge from the arrival of Lithium Iron Phosphate batteries: the discharge currents are equivalent, but in the case of LiFePO4, this current is constant until the battery is discharged completely. In the case of a lead-acid battery, the greater the discharge current, the more the usable capacity of the battery is reduced.
This is a table showing the usable capacities of the 2 technologies depending on the discharge speed (and therefore the current):
| Discharge speed |
Discharge current(*) |
Usable capacity | |
| Lead-acid | LiFePO4 | ||
| 20 hours | C/20 | 100% | 100% |
| 1 hour | C | 55% | 100% |
| 6 minutes | 10x C | 35% | 92% |
| 3 minutes | 20x C | 27% | 90% |
| 1.5 minutes | 40x C | 16% | 80% |
(*) The current "C" corresponds to the stated battery capacity: for a 65 Ah battery, C = 65A
With its clearly superior performance, the "theoretical" capacity of the LiFePO4 battery can be reduced by a factor of between 3 and 7 compared with the lead-acid battery - for the same application.
Strong points of the 2 technologies
| Reduced volume (factor between 2 and 5) | |
| Reduced weight (divided by 7) | |
| Extended working life (2 to 5 times more cycles) | |
| Auto-discharge very low if not used | |
| Very fast recharge | |
| Does not contain acid | |
| Does not contain toxic substances | |
| Less expensive to buy | Less expensive per cycle |
| Zero maintenance |
Recommended applications:
Motorcycle, wheelchair, golf buggy, ULM, watersports, scooter, camper, etc.