Technical Characteristics of Prismatic Sodium Battery Cells

I. Technical Performance and Parameters of Prismatic Sodium Ion Cell(NFPP)
- Energy efficiency of Prismatic Sodium Ion Cell is more than 96% under 0.5P rate and discharge @ 60℃
Specifications:
1) Charge energy≥Initial charge energy *98%
2) Discharge energy ≥ Initial discharge energy *98%
3) Energy efficiency≥93%

| Prismatic Sodium Ion Cell | Charge capacity(Ah) | Charge energy(Wh) | Discharge capacity(Ah) | Discharge energy(Wh) | Capacity efficiency | Energy efficiency (>93%) |
| 1# | 160.88 | 482.8 | 163.46 | 467.45 | 101.61% | 96.82% |
| 2# | 161.12 | 484.6 | 163.61 | 466.53 | 101.54% | 96.27% |
- Energy efficiency of Prismatic Sodium Ion Cell is more than 85% under 0.5P rate and discharge @ -40℃
Specifications:
1) Charge energy≥ Initial charge energy *90%
2) Discharge energy ≥ Initial discharge energy *80%
3) Energy efficiency ≥85%

| Prismatic Sodium Ion Cell | Charge capacity(Ah) | Charge energy(Wh) | Discharge capacity(Ah) | Discharge energy(Wh) | Capacity efficiency | Energy efficiency (>85%) |
| 1# | 153.52 | 477.03 | 149.98 | 418.33 | 97.69% | 87.69% |
| 2# | 153.91 | 476.40 | 150.22 | 421.76 | 97.60% | 88.53% |
- Prismatic Sodium Ion Cell Supports Discharge rate from 1P to 2P, capacity energy is more than 98%, while energy efficiency is more than 90%
Specifications:
1) 0.5P energy efficiency rate ≥93%
2) 1P energy retention rate ≥95%
3) 1P energy efficiency rate ≥90%.

- Energy retention rate of Prismatic Sodium Ion Cell is more than 95% after standardized charging (100% SOC), storage 30 days@45℃.

- Charge/Discharge energy recovery rate of Prismatic Sodium Ion Cell is more than 96% after standardized charging, discharge to 50%SOC, storage 30 days@ 50℃

- Charge/Discharge energy recovery rate of Prismatic Sodium Ion Cell is more than 70% at 10000 times,with 0.5P charging/0.5P discharging cycle life @25℃
Specifications:
1)Charge/discharge energy retention rate≥80% at 6000 times;
2)Charge/discharge energy retention rate≥70% at 10000 times .


- Charge/Discharge energy recovery rate of Prismatic Sodium Ion Cell is more than 80% at 3000 times,with 1P charging/1P discharging cycle life @25℃
Specification:
Charge/discharge energy retention rate≥80% at 3000 times.


- Charge/Discharge energy recovery rate of Prismatic Sodium Ion Cell is more than 80% at 2000 times,with 0.5P charging/0.5P discharging cycle life @60℃
Specification:
Charge/discharge energy retention rate≥80% at 2000 times.


II. Safety Performance and test of Prismatic Sodium Ion Cell(NFPP)
- Short Circuit Test, No fire and No explosion of Prismatic Sodium Ion Cell
Test procedure: After standardized charging, the cell shall be subjected to one short circuit condition with a total external resistance of less than 1mΩ for 10min. Then the cell shall be observed for 1h.

| Prismatic Sodium Ion Cell | Max temp (℃) | Initial cell OCV(V) | Initial cell ACIR(mΩ) | After test OCV(V) | After test ACIR(mΩ) | Result |
| 1# | 364 | 3.195 | 0.21 | 1.583 | 0.23 | No fire, no explosion |
- Over charge Test, No fire and No explosion of Prismatic Sodium Ion Cell
Test procedure: After standardized charging, the cell shall be charged with a constant current 0.5C to a final voltage 5.175V or the test time reaches 1h. Then the cell shall be observed for 1h.

| Prismatic Sodium Ion Cell | Max temp (℃) | Initial cell OCV(V) | Initial cell ACIR(mΩ) | After test OCV(V) | After test ACIR(mΩ) | Result |
| 1# | 73.6 | 3.220 | 0.21 | 3.330 | 1.28 | No fire, no explosion |
- Over discharge Test, No fire and No explosion of Prismatic Sodium Ion Cell
Test procedure: After standardized discharging, the cell shall be discharged with a constant current 0.5C until the test time reaches 1h. Then the cell shall be observed for 1h.

| Prismatic Sodium Ion Cell | Max temp (℃) | Initial cell OCV(V) | Initial cell ACIR(mΩ) | After test OCV(V) | After test ACIR(mΩ) | Result |
| 1# | 37.6 | 2.220 | 0.21 | 1.436 | 0.22 | No fire, no explosion |
- Nail testing, No fire and No explosion of Prismatic Sodium Ion Cell
Test procedure: After standardized charging, the cell shall be vertically penetrated by a steel nail with a diameter of 5mm at 25mm/s. The nail shall be hold for 1h and then the cell shall be observed for 1h.




