The BAK INR4695-330B battery cell is one of the ever increasing number of 46xx format cells. Based on the date on the specification sheet the start of production is 2023.
Metrics
- Energy density
- Gravimetric = 275 Wh/kg
- Volumetric = 754 Wh/litre
- Power density
- Gravimetric = 2790 W10s/kg
Specifications
- Nominal Capacity = 33 Ah
- Minimum capacity = 32 Ah
- Nominal Voltage = 3.6 V
- Maximum charge voltage = 4.2 V
- Minimum discharge voltage = 2.5 V
- Nominal Energy = 119 Wh
- Dimensions
- Diameter = 46mm
- Height = 95mm
- Mass = 0.43 kg
Power9 Tech kindly provided us with the images of the cell teardown and their findings from this process.
Regarding BAK 4695 battery cell teardown information, we can share them as below images showing the cell tab design.
Some findings from the teardown activity:
- The positive and negative tabs are not subjected to the flattening process.
- The positive and negative current collectors are connected to the positive and negative electrode tabs via vertical welding 5 pcs of laser-welding lines, dimension: 16mm×1mm each;
- The negative current collector is connected to the steel case via spot laser welding (with 12 welding spots).
Charge/Discharge
- Discharge
- Maximum continuous = 132 A (4C)
- Peak power = 1200 W10s
- Temperature range
- Max = 60 °C
- Min = -30 °C
- Charge
- Maximum continuous = 132 A (4C)
- Temperature range
- Max = 45 °C
- Min = 0 °C
- 10 to 80% Fast Charge Time = 15 minutes
- Resistance
- DCIR 10s = 0.00275 Ohms @25 C 50%SoC
- ACIR = 0.0015 Ohms @1kHz
- Storage temperature
- Max = 25 °C
- Min = -30 °C
- Calendar Ageing
- 90 days @ 100% SoC @ 25°C = 97% SoH
- Cycle Ageing
- 1000 cycles (0.5C charge / 1C discharge) to 80% SoH
This post has been built based on the support of and sponsorship from: Resonate Testing Ltd, Quarto Technical Services, Eatron Technologies and About:Energy
plus the kind support of Power9 Tech for supplying the teardown images and narrative
References
- BAK INR4695 Specification Sheet