Lithium-iron-phosphate is the safest of the mainstream li-ion battery types. The nominal voltage of a LFP cell is 3,2V (lead-acid: 2V/cell). A 12,8V LFP battery therefore consists of 4 cells connected in series; and a 25,6V battery consists of 8 cells connected in series.
- Efficient: In several applications (especially off-grid solar and/or wind), energy efficiency can be of crucial importance. The round trip energy efficiency (discharge from 100% to 0% and back to 100% charged) of the average leadacid battery is 80%. The round trip energy efficiency of a LFP battery is 92%.
- Reduction in weight: Saves up to 70% in space compared to lead batteries (with equivalent energy used).
- Expensive? LFP batteries are expensive when compared to lead-acid. But in demanding applications, the high initial cost will be more than compensated by longer service life, superior reliability and excellent efficiency.
The LFP batteries have integrated cell balancing and cell monitoring. Up to 5 batteries can be paralleled and up to four batteries can be series connected so that a 48V battery bank of up to 1500Ah can be assembled. The cell balancing/monitoring cables can be daisychained and must be connected to a Battery Management System (BMS).
Battery Management System (BMS)
The BMS will:
1. Disconnect or shut down the load whenever the voltage of a battery cell decreases to less than 2,5V.
2. Stop the charging process whenever the voltage of a battery cell increases to more than 4,2V.
3. Shut down the system whenever the temperature of a cell exceeds 50°C. See the BMS datasheets for more features.
Nominal volgate (Nv): 12.8V
Nominal capacity @ 25°C*: 60Ah
Nominal capacity @ 0°C*: 48Ah
Nominal capacity @ -20°C*: 30Ah
Nominal energy @ 25°C*: 768Wh
*Discharge current ≤1C
CYCLE LIFE (capacity ≥ 80% of nominal)
80% DoD 2500 cycles
70% DoD 3000 cycles
50% DoD 5000 cycles
Maximum continuous discharge current: 120A
Recommended continuous discharge current: ≤60A
End of discharge voltage: 11V
Operating Temperature Discharge: -20°C at +50°C Charge: +5°C at +50°C
Storage Temperature: -45°C - +70°C
Humidity (non condensing) Max. 95%
Protection Class IP 22
Charge voltage: Between 14V/28V and 14,4V/28,8V (14,2V/28,4V reccomended)
Float charge: 13,5V/27V
Max charge current: 120A
Recommended charge current: ≤30A
Max storage time at 25°C* (*when completely charged): 1 year
BMS connection: Male + female cable with M8 circular connector, length 50cm
Power connection (threaded inserts): M8
Dimensions (HxLxW) in mm: 240x285x132