Lithium-ion (Li-ion) batteries have several advantages over conventional lead-acid batteries:
High energy density: more energy with less weight
High charge currents (shortens the charge period)
High discharge currents (enabling for example electrical cooking on a small battery bank)
Long battery life (up to six times the battery life of a conventional battery)
High efficiency between charging and discharging (very little energy loss due to heat development)
- Higher continuous power available
- A lead-acid battery can fail prematurely due to sulphation if it is left partially charged, fully discharged, or rarely fully charged for long periods of time.
- A Lithium-ion battery does not need to be fully charged, has a wide operating temperature range and excellent cycling performance.
- They are therefore the battery for very demanding applications.
- The typical energy efficiency (energy that can be taken out of the battery compared to energy required to re-charge) for lead acid batteries is ~ 80%.
- For a Li-ion battery it is ~ 92%
- The final 20% charge for a lead-acid battery is particularly inefficient with efficiencies of ~ 50% and can take a very long time for the battery to become completely charged.
- In contrast a Li-ion battery can still achieve 90% efficiency and so can be fully charged more quickly and using les energy.
Size & Weight
- Li-ion batteries save up to 70% in space and 70% in weight compared to lead-acid.
- Li-ion batteries are expensive when compared to lead-acid, but can be compensated for by longer service life, size or weight considerations, superior reliability & efficiency.
Battery Management System
- It is vital that the correct battery management system (BMS) is used to control the battery charging. This is important to actively balance the individual cells that make up the battery and prevent under or over voltage which can otherwise destroy the battery.