Methods and systems for recharging a battery

• US 10,291,051 B2
• Filed: 01/13/2014
• Issued: 05/14/2019
• Est. Priority Date: 01/11/2013
• Status: Active Grant

• Current Assignee: RIOT Energy Incorporated
• Original Assignee: ZPower, LLC
• Inventors: Pourdarvish, Reza, Renken, Troy W., Powers, Timothy W.
• Primary Examiner(s): Isla, Richard
• Assistant Examiner(s): Torres Ruiz, Johali A
• Application Number:
  US14/759,666
• Publication Number:
  US 20150357859A1
• Time in Patent Office: 1,947 Days
• Field of Search: 320159
• CPC Class Codes: H01M 10/32 Silver accumulators H01M10/34 takes precedence
• CPC Class Codes: H01M 10/44 Methods for charging or discharging circuits for charging H02J7/00
• CPC Class Codes: H02J 7/0071 with a programmable schedule
• CPC Class Codes: H02J 7/00712 the cycle being controlled or terminated in response to electric parameters
• CPC Class Codes: H02J 7/007182 in response to battery voltage
• CPC Class Codes: H02J 7/007184 in response to battery voltage gradient
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

The present invention provides a novel method for charging silver-zinc rechargeable batteries and an apparatus for practicing the charging method. The recharging apparatus includes recharging management circuitry; and one or more of a silver-zinc cell, a host device or a charging base that includes the recharging management circuitry. The recharging management circuitry provides means for regulating recharging of the silver-zinc cell, diagnostics for evaluating battery function, and safety measures that prevent damage to the apparatus caused by charging batteries composed of materials that are not suited for the charging method (e.g., non-silver-zinc batteries).

Claims

1. A method of charging a rechargeable battery having multiple voltage plateaus wherein the battery has a voltage, V_Batt, that is less than its highest voltage plateau comprising:

a1) Charging the battery with a charging current, I₁, wherein the charging current, I₁, is applied until the battery is charged to a first voltage, V₁;

b1) Controlling the charging current, I₁, when the voltage of the battery is V₁, so that the voltage of the battery is maintained at V₁ with a deviation of no more than about ±

20% of V₁; and

c1) Monitoring for each of the following occurrences and arresting the charging current, I₁, at the first of the following occurrences

1) the battery has been charged with charging current, I₁, for a period of 9 hrs±

3 hrs;

2) the battery has been charged with a target capacity C_T by the charging current, I₁;

or

3) the charging current, I₁, has an amperage of about 15% or less of its highest amperage, I_max, after the battery is charged with I₁ for a period, T₁, of from about 60 min to about 240 min,

wherein V₁ is less than the voltage of a natural polarization peak, V_PP;

wherein V_PP is associated with a voltage plateau, V_P, wherein V_P is greater than V_Batt, and V₁ is greater than V_P;

wherein C_T is calculated according to equation (7) and inequality (8)

C_T=m×

t₀+C_min and 

 

(7)

C_T≤

C_R 

 

(8)

wherein t₀ is the time required to charge the battery from a voltage of V_Batt to V₁, m is from about 0.01 mAh/min to about 10 mAh/min, C_min is from about 5 mAh to about 200 mAh, and C_R is the rated capacity of the battery.

2. The method of claim 1, wherein m is from about 0.1 mAh/min to about 1 mAh/min.

3. The method of claim 2, wherein m is from about 0.15 mAh/min to about 0.45 mAh/min.

4. The method of claim 1, wherein C_min is from about 10 mAh to about 200 mAh.

5. The method of claim 4, wherein C_min is from about 5 mAh to about 20 mAh.

6. The method of claim 5, wherein C_min is from about 13 mAh to about 17 mAh.

7. The method of claim 1, wherein C_R is at least about 20 mAh.

8. The method of claim 7, wherein C_R is from about 25 mAh to about 150 mAh.

9. The method of claim 1, wherein I₁ is substantially constant until the battery is charged to voltage V₁.

10. The method of claim 1, wherein charging current, I₁, is sufficient to charge the battery to voltage V₁ in a period of from about 1 min to about 300 min when the battery'"'"'s initial SOC is less than about 40% of its rated capacity.

11. The method of claim 10, wherein charging current, I₁, is sufficient to charge the battery to voltage V₁ in a period of from about 5 min to about 240 min when the battery'"'"'s initial SOC is less than about 40% of its rated capacity.

12. The method of claim 1, wherein charging current, I₁, has a maximum amperage, I_max, of at least about 3 mA.

13. The method of claim 12, wherein charging current, I₁, has a minimum amperage, I_min, of from about 0.25 mA to about 0.60 mA.

14. The method of claim 1, further comprising calculating a remaining charge capacity, C_rem, according to equation (10a):

C_rem=C_T−

(I₁×

t₀)/60 

 

(10a).

15. The method of claim 1, wherein V₁ is greater than about 1.80 V.

16. The method of claim 15, wherein V₁ is from about 1.85 V to about 2.05 V.

17. The method of claim 16, comprising controlling the charging current, I₁, when the voltage of the battery is V₁, so that the voltage of the battery is maintained at V₁ with a deviation of no more than about ±

10% of V₁.

18. The method of claim 1, further comprising step d5):

arresting the charging current, I₁, if the battery has not been charged to a voltage of at least about 75% of V₁ after a period of from about 20 min to about 60 min.

19. The method of claim 18, further comprising step e5):

activating an alert if the battery has not been charged to a voltage of at least about 75% of V₁ after a period of from about 20 min to about 60 min.

20. The method of claim 1, further comprising step d6):

arresting the charging current I₁, if the charging current, I₁, is not at least I_max±

10% after a period, T₁, of from about 60 min to about 240 min, and the OCV of the battery is less than about 93% of V₁ after a resting period of at least about 2.0 min.

21. The method of claim 20, further comprising step e6):

activating an alert if the charging current, I₁, is not at least I_max±

10% after a period, T₁, of from about 60 min to about 240 min, and the OCV of the battery is less than about 93% of V₁ after a resting period of at least about 2.0 min.

22. The method of claim 1, further comprising

g) Activating an alert when the charging current, I₁, has an amperage that is about 20% or less of its highest amperage, I_max, after the battery is charged with I₁ for a period, T₁, of from about 60 min to about 240 min.

23. The method of claim 22, further comprising

g) Activating an alert when the charging current, I₁, has an amperage that is about 15% or less of its highest amperage, I_max, after the battery is charged with I₁ for a period, T₁, of from about 60 min to about 240 min.

24. The method of claim 23, further comprising

g) Activating an alert when the charging current, I₁, has an amperage that is about 11% or less of its highest amperage, I_max, after the battery is charged with I₁ for a period, T₁, of from about 65 min to about 75 min.

25. The method of claim 1, further comprising

g) Activating an alert when the charging current, I₁, is 0.5 mA±

0.1 mA after the battery is charged with I₁ for a period of at least about 70 min.

26. The method of claim 1, further comprising

h) Activating an alert when the voltage of the battery, V_Batt, is less than about 98% of V₁ for a continuous period of more than about 1.5 min and the charging current, I₁, has an amperage that is at least about 70% of its highest amperage, I_max, during this continuous period.

27. The method of claim 1, further comprising

h) Activating an alert when the voltage of the battery, V_Batt, is less than about 96% of V₁ for a continuous period of more than about 1.5 min, and the charging current, I₁, has an amperage that is at least about 80% of its highest amperage, I_max, during this continuous period.

28. The method of claim 1, further comprising

h) Activating an alert when the voltage of the battery, V_Batt, is less than about 1.95 V for a continuous period of from about 1.5 min to about 5 min and the charging current, I₁, is greater than about 80% of its highest value during this continuous period.

29. The method of claim 1, further comprising

i) activating an alert when the voltage of the battery, V_Batt, is less than about 1.0 V for a continuous period of about 5 seconds or more when the battery is charged with charging current I₁.

30. The method of claim 1, further comprising

d4) Charging the battery with a diagnostic charge current, I_Diag, for a period of about 10 seconds or less;

and

e4) Discontinuing the recharging of the battery if Δ

V≤

−

m_d×

V_d0+b_d, wherein

Δ

V=V_d1−

V_d0 

 

(11);

0.1≤

m_d≤

0.99 

 

(12a);

0.75≤

b_d≤

0.95 

 

(13);

I_Diag is from about 2 mA to about 20 mA, V_d0 is the voltage of the battery prior to being charged with I_Diag; and

V_d1 is the voltage of the battery after it is charged with I_Diag.