Fast formation cycling for rechargeable batteries

1. A method for fast formation lithium ion cycling for rechargeable batteries including at least one cell, comprising the steps of:

1) charging the cell from open-circuit voltage (OCV) up to 80-90% of an upper cutoff voltage (UCV) of from 4-5 V at a charging (C) rate not less than 0.5 C and not more than 1.5 C;

2) charging the cell from 80-90% of UCV to 97-100% of UCV at a charging (C) rate of not less than 0.2 C and not more than 0.5 C;

3) discharging the cell from 97-100% of UCV to 80-90% of UCV at a discharging (C) rate of not less than 0.2 C and not more than 0.5 C; and,

repeating steps 2) and 3) up to 2-10 times where the charging and discharging rates are progressively increased by 25-75%.

2. The method of claim 1 , wherein the cell comprises LiNi x Mn y Co 1-x-y (NMC)/Graphite, wherein x≤0.5 and y≤0.4, and the method comprises the steps of:

1) charging the cell from open-circuit voltage (OCV) of ˜3 V up to 3.7-3.9 V at a C rate not less than 0.5 C (80 mA/g-NMC) and not more than 1.5 C (240 mA/g-NMC);

2) charging the cell from 3.7-3.9 V to maximum cell voltage of 4.2-4.3 V at a C rate of not less than 0.2 C (32 mA/g-NMC) and not more than 0.5 C (80 mA/g-NMC); and

3) discharging the cell from 4.2-4.3 V to 3.7-3.9 V at a C rate of not less than 0.2 C (32 mA/g-NMC) and not more than 0.5 C (80 mA/g-NMC).

3. The method of claim 2 , further comprising the steps of:

4) charging the cell from 3.7-3.9 V to maximum cell voltage of 4.2-4.3 V at a C rate of not less than 0.5 C (80 mA/g-NMC) and not more than 0.75 C (120 mA/g-NMC);

5) discharging the cell from 4.2-4.3 V to 3.7-3.9 V at a C rate of not less than 0.5 C (80 mA/g-NMC) and not more than 0.75 C (120 mA/g-NMC).

4. The method of claim 3 , further comprising the steps of:

6) charging the cell from 3.7-3.9 V to maximum cell voltage of 4.2-4.3 V at a C rate of not less than 0.75 C (120 mA/g-NMC) and not more than 1.2 C (192 mA/g-NMC); and

7) discharging the cell from 4.2-4.3 V to 3.7-3.9 V at a C rate of not less than 0.75 C (120 mA/g-NMC) and not more than 1.2 C (192 mA/g-NMC).

5. The method of claim 4 , further comprising the steps of:

8) charging the cell from 3.7-3.9 V to maximum cell voltage of 4.2-4.3 V at a C rate of not less than 1.2 C (192 mA/g-NMC) and not more than 1.5 C (240 mA/g-NMC); and

9) discharging the cell from 4.2-4.3 V to 3.7-3.9 V at a C rate of not less than 1.2 C (192 mA/g-NMC) and not more than 1.5 C (240 mA/g-NMC).

6. The method of claim 5 , further comprising the steps of:

10) charging the cell from 3.7-3.9 V to maximum cell voltage of 4.2-4.3 V at a C rate of not less than 1.5 C (240 mA/g-NMC) and not more than 2.0 C (320 mA/g-NMC); and

11) discharging the cell from 4.2-4.3 V to 2.5 V at a C rate not less than 0.5 C (80 mA/g-NMC) and not more than 1.5 C (240 mA/g-NMC).

7. The method of claim 1 , wherein the cell comprises LiNi x Mn y Co 1-x-y O 2 (NMC)/Graphite, wherein 0.5≤x≤1.8 and 0.1≤y≤0.4, and the method comprises the steps of:

1) charging the cell from open-circuit voltage (OCV) of ˜3 V up to 3.7-3.9 V at a C rate not less than 0.5 C (95 mA/g-NMC) and not more than 1.5 C (285 mA/g-NMC);

2) charging the cell from 3.7-3.9 V to maximum cell voltage of 4.2-4.4 V at a C rate of not less than 0.2 C (38 mA/g-NMC) and not more than 0.5 C (95 mA/g-NMC); and

3) discharging the cell from 4.2-4.4 V to 3.7-3.9 V at a C rate of not less than 0.2 C (38 mA/g-NMC) and not more than 0.5 C (95 mA/g-NMC).

8. The method of claim 7 , further comprising the steps of:

4) charging the cell from 3.7-3.9 V to maximum cell voltage of 4.2-4.4 V at a C rate of not less than 0.5 C (95 mA/g-NMC) and not more than 0.75 C (142.5 mA/g-NMC); and

5) discharging the cell from 4.2-4.4 V to 3.7-3.9 V at a C rate of not less than 0.5 C (95 mA/g-NMC) and not more than 0.75 C (142.5 mA/g-NMC).

9. The method of claim 8 , further comprising the steps of:

6) charging the cell from 3.7-3.9 V to maximum cell voltage of 4.2-4.4 V at a C rate of not less than 0.75 C (142.5 mA/g-NMC) and not more than 1.2 C (228 mA/g-NMC); and

7) discharging the cell from 4.2-4.4 V to 3.7-3.9 V at a C rate of not less than 0.75 C (142.5 mA/g-NMC) and not more than 1.2 C (228 mA/g-NMC).

10. The method of claim 9 , further comprising the steps of:

8) charging the cell from 3.7-3.9 V to maximum cell voltage of 4.2-4.4 V at a C rate of not less than 1.2 C (228 mA/g-NMC) and not more than 1.5 C (285 mA/g-NMC); and

9) discharging the cell from 4.2-4.4 V to 3.7-3.9 V at a C rate of not less than 1.2 C (228 mA/g-NMC) and not more than 1.5 C (285 mA/g-NMC).

11. The method of claim 10 , further comprising the steps of:

10) charging the cell from 3.7-3.9 V to maximum cell voltage of 4.2-4.4 V at a C rate of not less than 1.5 C (285 mA/g-NMC) and not more than 2.0 C (380 mA/g-NMC); and

11) discharging the cell from 4.2-4.4 V to 2.5 V at a C rate not less than 0.5 C (95 mA/g-NMC) and not more than 1.5 C (285 mA/g-NMC).

12. The method of claim 1 , wherein the cell comprises LiFePO 4 (LFP)/graphite and the method comprises the steps of:

1) charging the cell from open-circuit voltage (OCV) of ˜2.5 V up to 3.2-3.4 V at a C rate not less than 0.5 C (75 mA/g-LFP) and not more than 1.5 C (225 mA/g-LFP);

2) charging the cell from 3.2-3.4 V to maximum cell voltage of 3.6-3.7 V at a C rate of not less than 0.2 C (30 mA/g-LFP) and not more than 0.5 C (75 mA/g-LFP); and

3) discharging the cell from 3.6-3.7 V to 3.2-3.4 V at a C rate of not less than 0.2 C (30 mA/g-LFP) and not more than 0.5 C (75 mA/g-LFP).

13. The method of claim 12 , further comprising the steps of:

4) charging the cell from 3.2-3.4 V to maximum cell voltage of 3.6-3.7 V at a C rate of not less than 0.5 C (75 mA/g-LFP) and not more than 0.75 C (112.5 mA/g-LFP); and

5) discharging the cell from 3.6-3.7 V to 3.2-3.4 V at a C rate of not less than 0.5 C (75 mA/g-LFP) and not more than 0.75 C (112.5 mA/g-LFP).

14. The method of claim 13 , further comprising the steps of:

6) charging the cell from 3.2-3.4 V to maximum cell voltage of 3.6-3.7 V at a C rate of not less than 0.75 C (112.5 mA/g-LFP) and not more than 1.2 C (180 mA/g-LFP); and

7) discharging the cell from 3.6-3.7 V to 3.2-3.4 V at a C rate of not less than 0.75 C (112.5 mA/g-LFP) and not more than 1.2 C (180 mA/g-LFP).

15. The method of claim 14 , further comprising the steps of:

8) charging the cell from 3.2-3.4 V to maximum cell voltage of 3.6-3.7 V at a C rate of not less than 1.2 C (180 mA/g-LFP) and not more than 1.5 C (225 mA/g-LFP); and

9) discharging the cell from 3.6-3.7 V to 3.2-3.4 V at a C rate of not less than 1.2 C (180 mA/g-LFP) and not more than 1.5 C (225 mA/g-LFP).

16. The method of claim 15 , further comprising the steps of:

10) charging the cell from 3.2-3.4 V to maximum cell voltage of 3.6-3.7 Vat a C rate of not less than 1.5 C (225 mA/g-LFP) and not more than 2.0 C (300 mA/g-LFP); and

11) discharging the cell from 3.6-3.7 V to 2.5 V at a C rate not less than 0.5 C (75 mA/g-LFP) and not more than 1.5 C (225 mA/g-LFP).

17. The method of claim 1 , wherein the cell comprises LiNi x Co y Al 1-x-y O 2 (NCA)/Graphite, wherein 0.5<x≤0.85 and 0.1≤y<0.25, and the method comprises the steps of:

1) charging the cell from open-circuit voltage (OCV) of ˜3 V up to 3.7-3.9 V at a C rate not less than 0.5 C (100 mA/g-NCA) and not more than 1.5 C (300 mA/g-NCA);

2) charging the cell from 3.7-3.9 V to maximum cell voltage of 4.2-4.3 V at a C rate of not less than 0.2 C (40 mA/g-NCA) and not more than 0.5 C (100 mA/g-NCA); and

3) discharging the cell from 4.2-4.3 V to 3.7-3.9 V at a C rate of not less than 0.2 C (40 mA/g-NCA) and not more than 0.5 C (100 mA/g-NCA).

18. The method of claim 17 , further comprising the steps of:

4) charging the cell from 3.7-3.9 V to maximum cell voltage of 4.2-4.3 V at a C rate of not less than 0.5 C (100 mA/g-NCA) and not more than 0.75 C (150 mA/g-NCA); and

5) discharging the cell from 4.2-4.3 V to 3.7-3.9 V at a C rate of not less than 0.5 C (100 mA/g-NCA) and not more than 0.75 C (150 mA/g-NCA).

19. The method of claim 18 , further comprising the steps of:

6) charging the cell from 3.7-3.9 V to maximum cell voltage of 4.2-4.3 V at a C rate of not less than 0.75 C (150 mA/g-NCA) and not more than 1.2 C (240 mA/g-NCA); and

7) discharging the cell from 4.2-4.3 V to 3.7-3.9 V at a C rate of not less than 0.75 C (150 mA/g-NCA) and not more than 1.2 C (240 mA/g-NCA).

20. The method of claim 19 , further comprising the steps of:

8) charging the cell from 3.7-3.9 V to maximum cell voltage of 4.2-4.3 V at a C rate of not less than 1.2 C (240 mA/g-NCA) and not more than 1.5 C (300 mA/g-NCA); and

9) discharging the cell from 4.2-4.3 V to 3.7-3.9 V at a C rate of not less than 1.2 C (240 mA/g-NCA) and not more than 1.5 C (300 mA/g-NCA).

21. The method of claim 20 , further comprising the steps of:

10) charging the cell from 3.7-3.9 V to maximum cell voltage of 4.2-4.3 V at a C rate of not less than 1.5 C (300 mA/g-NCA) and not more than 2.0 C (400 mA/g-NCA); and

11) discharging the cell from 4.2-4.3 V to 2.5 V at a C rate not less than 0.5 C (100 mA/g-NCA) and not more than 1.5 C (300 mA/g-NCA).

22. The method of claim 1 , wherein the cell comprises LiCoO 2 (LCO)/graphite and the method comprises the steps of:

1) charging the cell from open-circuit voltage (OCV) of ˜3 V up to 3.7-3.9 V at a C rate not less than 0.5 C (70 mA/g-LCO) and not more than 1.5 C (210 mA/g-LCO);

2) charging the cell from 3.7-3.9 V to maximum cell voltage of 4.2-4.3 V at a C rate of not less than 0.2 C (28 mA/g-LCO) and not more than 0.5 C (70 mA/g-LCO); and

3) discharging the cell from 4.2-4.3 V to 3.7-3.9 V at a C rate of not less than 0.2 C (28 mA/g-LCO) and not more than 0.5 C (70 mA/g-LCO).

23. The method of claim 22 , further comprising the steps of:

4) charging the cell from 3.7-3.9 V to maximum cell voltage of 4.2-4.3 V at a C rate of not less than 0.5 C (70 mA/g-LCO) and not more than 0.75 C (105 mA/g-LCO); and

5) discharging the cell from 4.2-4.3 V to 3.7-3.9 V at a C rate of not less than 0.5 C (70 mA/g-LCO) and not more than 0.75 C (105 mA/g-LCO).

24. The method of claim 23 , further comprising the steps of:

6) charging the cell from 3.7-3.9 V to maximum cell voltage of 4.2-4.3 V at a C rate of not less than 0.75 C (105 mA/g-LCO) and not more than 1.2 C (168 mA/g-LCO); and

7) discharging the cell from 4.2-4.3 V to 3.7-3.9 V at a C rate of not less than 0.75 C (105 mA/g-LCO) and not more than 1.2 C (168 mA/g-LCO).

25. The method of claim 24 , further comprising the steps of:

8) charging the cell from 3.7-3.9 V to maximum cell voltage of 4.2-4.3 V at a C rate of not less than 1.2 C (168 mA/g-LCO) and not more than 1.5 C (210 mA/g-LCO); and

9) discharging the cell from 4.2-4.3 V to 3.7-3.9 V at a C rate of not less than 1.2 C (168 mA/g-LCO) and not more than 1.5 C (210 mA/g-LCO).

26. The method of claim 25 , further comprising the steps of:

10) charging the cell from 3.7-3.9 V to maximum cell voltage of 4.2-4.3 V at a C rate of not less than 1.5 C (210 mA/g-LCO) and not more than 2.0 C (280 mA/g-LCO); and

11) discharging the cell from 4.2-4.3 V to 2.5 V at a C rate not less than 0.5 C (70 mA/g-LCO) and not more than 1.5 C (210 mA/g-LCO).

27. The method of claim 1 , wherein the cell comprises Li 1+x Ni y Mn z Co 1-x-y-z O 2 (NMC)/graphite, wherein 0.01≤x≤0.2 and 0.1≤y<0.3 and 0.4<z≤0.65, and the method comprises the steps of:

1) charging the cell from open-circuit voltage (OCV) of ˜3 V up to 3.9-4.1 V at a C rate not less than 0.5 C (115 mA/g-NMC) and not more than 1.5 C (345 mA/g-NMC);

2) charging the cell from 3.9-4.1 V to maximum cell voltage of 4.3-4.5 V at a C rate of not less than 0.2 C (46 mA/g-NMC) and not more than 0.5 C (115 mA/g-NMC); and

3) discharging the cell from 4.3-4.5 V to 3.9-4.1 V at a C rate of not less than 0.2 C (46 mA/g-NMC) and not more than 0.5 C (115 mA/g-NMC).

28. The method of claim 27 , further comprising the steps of:

4) charging the cell from 3.9-4.1 V to maximum cell voltage of 4.3-4.5 V at a C rate of not less than 0.5 C (115 mA/g-NMC) and not more than 0.75 C (172.5 mA/g-NMC); and

5) discharging the cell from 4.3-4.5 V to 3.9-4.1 V at a C rate of not less than 0.5 C (115 mA/g-NMC) and not more than 0.75 C (172.5 mA/g-NMC).

29. The method of claim 28 , further comprising the steps of:

6) charging the cell from 3.9-4.1 V to maximum cell voltage of 4.3-4.5 V at a C rate of not less than 0.75 C (172.5 mA/g-NMC) and not more than 1.2 C (276 mA/g-NMC); and

7) discharging the cell from 4.3-4.5 V to 3.9-4.1 V at a C rate of not less than 0.75 C (172.5 mA/g-NMC) and not more than 1.2 C (276 mA/g-NMC).

30. The method of claim 29 , further comprising the steps of:

8) charging the cell from 3.9-4.1 V to maximum cell voltage of 4.3-4.5 V at a C rate of not less than 1.2 C (276 mA/g-NMC) and not more than 1.5 C (345 mA/g-NMC); and

9) discharging the cell from 4.3-4.5 V to 3.9-4.1 V at a C rate of not less than 1.2 C (276 mA/g-NMC) and not more than 1.5 C (345 mA/g-NMC).

31. The method of claim 30 , further comprising the steps of:

10) charging the cell from 3.9-4.1 V to maximum cell voltage of 4.3-4.5 V at a C rate of not less than 1.5 C (345 mA/g-NMC) and not more than 2.0 C (460 mA/g-NMC); and

11) discharging the cell from 4.3-4.5 V to 2.5 V at a C rate not less than 0.5 C (115 mA/g-NMC) and not more than 1.5 C (345 mA/g-NMC).

32. The method of claim 1 , wherein the cell comprises LiNi x Fe y Al 1-x-y O 2 (NFA)/graphite, wherein 0.5<x≤18 and 0.1≤y<0.4, and the method comprises the steps of:

1) charging the cell from open-circuit voltage (OCV) of ˜3 V up to 3.7-3.9 V at a C rate not less than 0.5 C (100 mA/g-NFA) and not more than 1.5 C (300 mA/g-NFA);

2) charging the cell from 3.7-3.9 V to maximum cell voltage of 4.2-4.3 V at a C rate of not less than 0.2 C (40 mA/g-NFA) and not more than 0.5 C (100 mA/g-NFA); and

3) discharging the cell from 4.2-4.3 V to 3.7-3.9 V at a C rate of not less than 0.2 C (40 mA/g-NFA) and not more than 0.5 C (100 mA/g-NFA).

33. The method of claim 32 , further comprising the steps of:

4) charging the cell from 3.7-3.9 V to maximum cell voltage of 4.2-4.3 V at a C rate of not less than 0.5 C (100 mA/g-NFA) and not more than 0.75 C (150 mA/g-NFA); and

5) discharging the cell from 4.2-4.3 V to 3.7-3.9 V at a C rate of not less than 0.5 C (100 mA/g-NFA) and not more than 0.75 C (150 mA/g-NFA).

34. The method of claim 33 , further comprising the steps of:

6) charging the cell from 3.7-3.9 V to maximum cell voltage of 4.2-4.3 V at a C rate of not less than 0.75 C (150 mA/g-NFA) and not more than 1.2 C (240 mA/g-NFA); and

7) discharging the cell from 4.2-4.3 V to 3.7-3.9 V at a C rate of not less than 0.75 C (150 mA/g-NFA) and not more than 1.2 C (240 mA/g-NFA).

35. The method of claim 34 , further comprising the steps of:

8) charging the cell from 3.7-3.9 V to maximum cell voltage of 4.2-4.3 V at a C rate of not less than 1.2 C (240 mA/g-NFA) and not more than 1.5 C (300 mA/g-NFA); and

9) discharging the cell from 4.2-4.3 V to 3.7-3.9 V at a C rate of not less than 1.2 C (240 mA/g-NFA) and not more than 1.5 C (300 mA/g-NFA).

36. The method of claim 35 , further comprising the steps of:

10) charging the cell from 3.7-3.9 V to maximum cell voltage of 4.2-4.3 V at a C rate of not less than 1.5 C (300 mA/g-NFA) and not more than 2.0 C (400 mA/g-NFA); and

11) discharging the cell from 4.2-4.3 V to 2.5 V at a C rate not less than 0.5 C (100 mA/g-NFA) and not more than 1.5 C (300 mA/g-NFA).

37. The method of claim 1 wherein a total time to perform the method is less than 48 hours.

38. A battery produced by the method of claim 1 , wherein the battery has no less than 95% rated capacity retention after 100 0.33C/−0.33C cycles.

39. The battery of claim 38 , wherein the battery has no less than 80% rated capacity retention after 1000 0.33C/−0.33C cycles.