Battery pack including electronic power saver

• US 5,675,232 A
• Filed: 05/06/1996
• Issued: 10/07/1997
• Est. Priority Date: 11/07/1989
• Status: Expired due to Fees

• Current Assignee: Unova Incorporated (Honeywell International Inc.)
• Original Assignee: Norand Corporation (Baker Hughes Company)
• Inventors: Koenck, Steven E.
• Primary Examiner(s): TSO, EDWARD H
• Application Number:
  US08/643,392
• Time in Patent Office: 519 Days
• Field of Search: 320/2, 320/13, 320/6, 320/15, 320/39, 429/96, 429/97, 429/98, 429/99, 429/100, 307/150
• US Class Current: 307/150
• CPC Class Codes: H01M 10/42 Methods or arrangements for servicing or maintenance of secondary cells or secondary half-cells H01M10/60 takes precedence
• CPC Class Codes: H01M 10/425 Structural combination with electronic components, e.g. electronic circuits integrated to the outside of the casing printed circuits H05K1/00
• CPC Class Codes: H01M 50/213 adapted for cells having curved cross-section, e.g. round or elliptic H01M50/209, H01M50/216 take precedence
• CPC Class Codes: H01M 50/227 Organic material
• CPC Class Codes: H01M 50/271 Lids or covers for the racks or secondary casings
• CPC Class Codes: H02J 2207/20 Charging or discharging characterised by the power electronics converter
• CPC Class Codes: H02J 7/007182 in response to battery voltage
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

A housing of a battery pack contains in addition to standard power cell elements a voltage converter. The voltage converter is interposed between the power cell elements and external output contacts of the housing. The voltage converter regulates the output voltage applied to the output contacts of the battery pack, such that the supply voltage of the battery pack remains at a predetermined value which is independent of the voltage supplied by the power cell elements to the voltage converter and does not vary over the discharge cycle of the power cell elements. Excess battery voltage available particularly during the initial portion of the discharge cycle of the power cell elements is efficiently converted to the predetermined output voltage value which reduces the overall current delivered by the power cells to extend the useful life of the battery pack between charges.

Claims

1. A battery pack comprising:

power cell having positive and negative terminals, the positive terminal having a positive voltage with respect to the voltage at the negative terminal, such positive voltage having values subject to measurable variations over a first range during a discharge cycle of the power cell;

housing means encasing the power cell, said housing means including external positive and negative contacts; and

regulating means, coupled respectively between the positive terminal of the power cell and the positive contact of the housing means, and between the negative terminal of the power cell and the negative contact of the housing means, for regulating the voltage at the positive terminal with respect to the voltage at the negative terminal of the power cell to values within a predetermined second range, and for applying such regulated values to the positive contact with respect to the negative contact of the housing means, whereby the power cell has between such positive and negative contacts a characteristic voltage variation of the predetermined range of values over the discharge cycle of the power cell;

wherein the regulating means is a switching type voltage converter and includes switch means operable to regulate the voltage at the positive contact of the housing means with respect to the negative contact, the switch means being connected between the positive contact and the positive terminal of the power cell, and in that the regulating means includes sensing means operable throughout the discharge cycle to sense the voltage requirements of a utilization device, connected between the positive and negative contacts of the housing means, and to control the regulating means to provide the appropriate voltage required by the utilization device.

2. A battery pack according to claim 1, wherein the power cell comprises of at least two power cell elements each of the power cell elements having positive and negative terminals.

3. A battery pack according to claim 2, wherein said housing means comprises a molded housing, including guide surfaces for inserting the power cell elements into said housing, and a cap for retaining the power cell elements within said housing, the cap including means for electrically coupling terminals to said voltage converter.

4. A battery pack according to claim 1 wherein the regulating means is a switching type voltage converter and the regulated voltage values are converted voltage values.

5. A battery pack according to claim 2 wherein the regulating means is a switching type voltage converter and the regulated voltage values are converted voltage values.

6. A battery pack according to claim 3 wherein the regulating means is a switching type voltage converter and the regulated voltage values are converted voltage values.

7. A battery pack according to claim 1, wherein the voltage converter comprises means, controlled by the output voltage appearing between the positive and negative contact of the housing means, for selectively applying power available at the respective terminals of the power cells to the contacts of the housing means, said selective power application means including a first capacitor coupled across the positive and negative contacts of the housing means, and a second capacitor coupled across the positive and negative terminals of the power cell.

8. A battery pack according to claim 2, wherein the voltage converter comprises means, controlled by the output voltage appearing between the positive and negative contact of the housing means, for selectively applying power available at the respective terminals of the power cells to the contacts of the housing means, said selective power application means including a first capacitor coupled across the positive and negative contacts of the housing means, and a second capacitor coupled across the positive and negative terminals of the power cell.

9. A battery pack according to claim 3, wherein the voltage converter comprises means, controlled by the output voltage appearing between the positive and negative contact of the housing means, for selectively applying power available at the respective terminals of the power cells to the contacts of the housing means, said selective power application means including a first capacitor coupled across the positive and negative contacts of the housing means, and a second capacitor coupled across the positive and negative terminals of the power cell.

10. A battery pack according to claim 2, wherein the housing means comprises means for receiving the power cell elements, means for supporting the voltage converter, and further including a circuit header board mounted within the housing, the circuit header including terminals and conductive extensions for electrically coupling the power cell elements to the voltage converter and means for electrically coupling the converted voltage values to the external contacts of the housing means.

11. A battery pack according to claim 2, wherein the voltage converter is a voltage converter module comprising a circuit board, and wherein said selective power application means is mounted on said circuit board and coupled module further comprising means mounted on said circuit board and coupled to said selective power application means for controlling the operation of the selective power application means.

12. A battery pack according to claim 2, further comprising a switch for selectively isolating the positive terminal of the power cell from being coupled to the voltage converter.

13. A battery pack according to claim 2, further comprising means for coupling a battery charger across the positive and negative terminals of the power cell, whereby a voltage applied to the terminals of the power cell is applied to the voltage converter for conversion to values within said predetermined second range for application to said external contacts of the housing.

14. A battery pack according to claim 2, wherein the housing means comprises a molded housing, said housing supporting the external negative contact disposed at a base of the housing and centered on a central axis through the housing and the external positive contact disposed in spaced relationship along said base adjacent a side wall of the housing, the housing further comprising guide means for receiving the voltage converter and the power cell elements, the housing means further comprising header means for electrically coupling the power cell elements to the voltage converter and means for electrically coupling the converted voltage values to the external contacts of the housing means.

15. A battery pack according to claim 14, wherein the positive external contact is a first positive external contact, the housing further supporting a second positive external contact spaced from the centered negative contact in symmetry to said first positive external contact.

16. A battery pack according to claim 2, wherein the regulating means comprises means for converting the positive voltage at the positive terminal with respect to the negative terminal of the power cell to a predetermined constant value over the discharge cycle of the power cell and for applying the converted voltage between the positive and negative external contacts.

17. A battery pack according to any of claims 2, which further comprises a power input terminal disposed in the housing and extending through the housing, an external portion of the power input terminal being adapted to be coupled to a positive power terminal of a battery charging device, the negative external contact being adapted to be coupled to the negative power terminal of the battery charging device, whereby a positive input voltage at a voltage, level in excess of the voltage level of the power cell applied to the positive terminal with respect to the negative terminal of the power cell for charging the power cell is converted by the voltage converting means prior to the voltage converting means applying the voltage to the positive external contact of the battery pack.

18. A battery pack according to claim 17, wherein the housing has a predetermined width between two opposite side walls, a base extending between the two side walls, the external contact and the power input terminal being spacedly disposed along the base, wherein a first one of the external contacts is centered along the base between the two opposite side walls and a second one of the external contact is spacedly located at a first, predetermined distance from the first external contact adjacent one of the side walls, and the power input terminal is spacedly located at a second predetermined distance from the centered first terminal.

19. A battery pack according to claim 18, wherein the first one of the external contacts is the negative contact, the positive power terminal is a first positive power terminal and the external portion thereof is a first positive contact, the housing including a second positive power terminal extending through the housing, a portion of the second positive power terminal being disposed externally of the housing and forming a second positive contact, the second positive contact being spacedly located at the first predetermined distance from the negative external contact adjacent the other side wall of the housing, the second predetermined distance being less than the first predetermined distance such that the power input terminal is located between the negative and one of the positive contacts of the battery pack, the means for converting the voltage and for applying the converted voltage including means for applying the converted voltage to the second positive external contact of the battery pack.

20. A battery pack according to claim 2, wherein the power cell is a plurality of power cell elements, the housing including means for slidably receiving the power cell elements, and wherein the means for converting the voltage at the positive terminals of the power cell and for applying the converted voltage to the positive external contact includes a voltage converter module, the voltage converter module having negative and positive input terminals and negative and positive output terminals, and means disposed within the housing adjacent a base of the housing for electrically coupling the power cell elements in series, thereby forming the power cell with the combined voltage of each of the power cell elements, means for coupling the negative and the positive terminals of the power cell to the respective input terminals of the voltage converter module, and means for coupling the output terminals of the voltage converter module to the respective external contact of the battery pack.

21. A battery pack according to claim 18, wherein the housing further includes means for slidably receiving the voltage converter module, the means for coupling including a resilient connector disposed adjacent an inner end of the means for slidably receiving the voltage converter module for coupling the inserted voltage converter module to the means for coupling, and wherein the battery pack further includes a cap adapted to retain the power cell elements and the voltage converter module within the housing, the cap including portions of the means for coupling the power cell elements in series.

22. A battery pack according to claim 2, wherein:

the regulating means comprises a voltage converter module having negative and positive input and output terminals;

wherein

said housing has spaced side walls, a base, an open end opposite the base, and means for receiving and for retaining the plurality of power cell elements and the voltage converter module within the housing; and

further comprises

means for coupling the plurality of power cell elements in series, thereby providing, a power cell having the combined voltage of the elements and negative and positive output terminals, means for coupling the negative and positive output terminals of the power cell to respective negative and positive input terminals of the voltage converter module, and means for coupling, the negative and positive output terminals of the voltage converter module to the respective negative and positive power contacts of the housing.

23. A battery utilization device battery regulation apparatus for operable connection between a battery and a battery utilization device, comprising a switching type voltage converter having

(1) a switch operable to regulate the voltage output of a battery wherein said switch regulates battery voltage output,

(2) a sensor for sensing the voltage requirements of a battery utilization device and for controlling said switch such that a battery utilization device connected to said apparatus while said apparatus is connected to a battery will receive the sensed required voltage over a portion of the discharge cycle of said battery.

24. The battery utilization device battery regulation apparatus of claim 23, wherein said portion of the discharge cycle includes both utilization periods wherein the battery output is both greater than and lesser than the voltage requirement of the battery utilization device.

25. The battery utilization device battery regulation apparatus of claim 24, wherein the output voltage of said apparatus is zero when the battery utilization device'"'"'s voltage requirement is zero.

26. The battery utilization device battery regulation apparatus of claim 23, wherein the voltage converter comprises a selector, controlled by the output voltage of the battery, for selectively applying power.

27. The battery utilization device battery regulation apparatus of claim 23, wherein said selector includes a capacitor.

28. A battery pack comprising:

power cell having positive and negative terminals, the positive terminal having a positive voltage with respect to the voltage at the negative terminal, such positive voltage having values subject to measurable variations over a first range during a discharge cycle of the power cell;

housing means encasing the power cell, said housing means including external positive and negative contacts;

regulating means, coupled respectively between the positive terminal of the power cell and the positive contact of the housing means, and between the negative terminal of the power cell and the negative contact of the housing means, for regulating the voltage at the positive terminal with respect to the voltage at the negative terminal of the power cell to values within a predetermined second range, and for applying such regulated values to the positive contact with respect to the negative contact of the housing means, whereby the power cell as between such positive and negative contacts a characteristic voltage variation of the predetermined second range of values over the discharge cycle of the power cell

characterized in that;

the regulating means is a switching type voltage converter and includes switch means operable to regulate the voltage at the positive contact of the housing means with respect to the negative contact, the switch means being connected between the positive contact and the positive terminal of the power cell, and in that the regulating means includes sensing means operable throughout the discharge cycle to sense the voltage requirements of a utilization device, connected between the positive and negative contacts of the housing means, and to control the regulating means to provide the appropriate voltage regulation required by the utilization device.

29. A battery pack according to claim 28, wherein the power cell comprises at least two power cell elements each of the power cell elements having positive and negative terminals.

30. A battery pack according to claim 29, wherein said housing means comprises a molded housing including guide surfaces for inserting the power cell elements into said housing, and a cap for retaining the power cell elements within said housing, the cap including means for electrically coupling terminals to said voltage converter.

31. A battery pack according to claim 28, wherein the voltage converter comprises means, controlled by the output voltage appearing between the positive and negative contacts of the housing means, for selectively applying power available at the respective terminals of the power cells to the contacts of the housing means, said selective power application means including a first capacitor coupled across the positive and negative contacts of the housing means, and a second capacitor coupled across the positive and negative terminals of the power cell.

32. A battery pack according to claim 28, wherein the housing means comprises means for receiving the power cell elements, means for supporting the voltage converter, and further including a circuit header board mounted within the housing, the circuit header board including terminals and conductive extensions for electrically coupling the power cell elements to the voltage converter and means for electrically coupling the converted voltage values to the external contacts of the housing means.

33. A battery pack according to claim 28, wherein the voltage converter is a voltage converter module comprising a circuit board, and wherein said selective power application means is mounted on said circuit board, the voltage converter module further comprising means mounted on said circuit board and coupled to said selective power application means for controlling the operation of the selective power application means.

34. A battery pack according to claim 28, further comprising a switch for selectively isolating the positive terminal of the power cell from being coupled to the voltage converter.

35. A battery pack according to claim 28, further comprising means for coupling a battery charger across the positive and negative terminals of the power cell, whereby a voltage applied to the terminals of the power cell is applied to the voltage converter for conversion to values within said predetermined second range for application to said external contact of the housing means.

36. A battery pack according to claim 28, wherein the housing means comprises a molded housing, said housing supporting the external negative contact disposed at a base of the housing and centered on a central axis through the housing and the external positive contact disposed in spaced relationship along said base adjacent a side wall of the housing, the housing further comprising guide means for receiving the voltage converter and the power cell elements, the housing means further comprising header means for electrically coupling the power cell elements to the voltage converter and means for electrically coupling the converted voltage values to the external contacts of the housing means.

37. A battery pack according to claim 35, wherein the positive external contact is a first positive external contact, the housing further supporting a second positive external contact spaced from the centered negative contact in symmetry to said first positive external contact.

38. A battery pack according to claim 28, wherein:

the regulating means comprising means for convening the positive voltage at the positive terminal with respect to the negative terminal of the power cell to a predetermined constant value over the discharge cycle of the power cell and for applying the converted voltage between the positive and negative external contacts.

39. A battery pack according to any of claims 28, which further comprises:

a power input terminal disposed in the housing and extending through the housing, an external portion of the power input terminal being adapted to be coupled to a positive power terminal of a battery charging device, the negative external contact being adapted to be coupled to the negative power terminal of the battery charging device, whereby a positive input voltage at a voltage level in excess of the voltage level of the power cell applied to the positive terminal with respect to the negative terminal of the power cell for charging the power cell is converted by the voltage converting means prior to the voltage converting means applying the voltage to the positive external contact of the battery pack.

40. A battery pack according to claim 39, wherein the housing has a predetermined width between two opposite side walls, a base extending between the two side walls, the external contacts and the power input terminal being spacedly disposed along the base, wherein a first one of the external contacts is centered along the base between the two opposite side walls and a second one of the external contacts is spacedly located at a first, predetermined distance from the first external contact adjacent one of the side walls, and the power input terminal is spacedly located at a second predetermined distance from the centered first terminal.

41. A battery pack according to claim 40, wherein the first one of the external contacts is the negative contact, the positive power terminal is a first positive power terminal and the external portion thereof is a first positive contact, the housing including a second positive power terminal extending through the housing, a portion of the second positive power terminal being disposed externally of the housing and forming a second positive contact, the second positive contact being spacedly located at the first predetermined distance from the negative external contact adjacent the other side wall of the housing, the second predetermined distance being less than the first predetermined distance such that the power input terminal is located between the negative and one of the positive contacts of the battery pack, the means for converting the voltage and for applying the converted voltage including means for applying the converted voltage to the second positive external contact of the battery pack.

42. A battery pack according to claim 28, wherein the power cell is a plurality of power cell elements, the housing including means for slidably receiving the power cell elements, and wherein the means for converting the voltage at the positive terminals of the power cell and for applying the converted voltage to the positive external contact includes a voltage converter module, the voltage converter module having negative and positive input terminals and negative and positive output terminals, and means disposed within the housing adjacent a base of the housing for electrically coupling the power cell elements in series, thereby forming the power cell with the combined voltage of each of the power cell elements, means for coupling the negative and the positive terminals of the power cell to the respective input terminals of the voltage converter module, and means for coupling the output terminals of the voltage converter module to the respective external contacts of the battery pack.

43. A battery pack according to claim 41, wherein the housing further includes means for slidably receiving the voltage converter module, the means for coupling including a resilient connector disposed adjacent an inner end of the means for slidably receiving the voltage converter module for coupling the inserted voltage converter module to the means for coupling, and wherein the battery pack further includes a cap adapted to retain the power cell elements and the voltage converter module within the housing, the cap including portions of the means for coupling the power cell elements in series.

44. A battery pack according to claim 29, wherein:

the regulating means comprises a voltage converter module having negative and positive input and output terminals;

wherein

said housing has spaced side walls, a base, an open end opposite the base, and means for receiving and for retaining the plurality of power cell elements and the voltage converter module within the housing; and

further comprises

means for coupling the plurality of power cell elements in series, thereby providing a power cell having the combined voltage of the elements and negative and positive output terminals, means for coupling the negative and positive output terminals of the power cell to respective negative and positive input terminals of the voltage converter module, and means for coupling the negative and positive output terminals of the voltage converter module to the respective negative and positive power contacts of the housing.

45. A battery pack comprising:

power cell having positive and negative terminals, the positive terminal having a positive voltage with respect to the voltage at the negative terminal, such positive voltage having values subject to measurable variations over a first range during a discharge cycle of the power cell;

a housing encasing the power cell, said housing including external positive and negative contacts; and

a regulator, coupled respectively between the positive terminal of the power cell and the positive contact of the housing, and between the negative terminal of the power cell and the negative contact of the housing, for regulating the voltage at the positive terminal with respect to the voltage at the negative terminal of the power cell to values within a predetermined second range, and for applying such regulated values to the positive contact with respect to the negative contact of the housing, whereby the power cell has between such positive and negative contacts a characteristic voltage variation of the predetermined range of values over the discharge cycle of the power cell;

wherein the regulator is a switching type voltage converter and includes a switch operable to regulate the voltage at the positive contact of the housing with respect to the negative contact, the switch being connected between the positive contact and the positive terminal of the power cell, and in that the regulator includes a sensor operable throughout the discharge cycle to sense the voltage requirements of a utilization device, connected between the positive and negative contacts of the housing, and to control the regulator to provide the appropriate voltage required by the utilization device.

46. A battery pack according to claim 45, wherein the power cell comprises of at least two power cell elements each of the power cell elements having positive and negative terminals.

47. A battery pack according to claim 46, wherein said housing comprises a molded housing, including guide surfaces for inserting the power cell elements into said housing, and a cap for retaining the power cell elements within said housing, the cap including for electrically coupling terminals to said voltage converter.

48. A battery pack according to claim 45 wherein the regulator is a switching type voltage converter and the regulated voltage values are converted voltage values.

49. A battery pack according to claim 45, wherein the voltage converter comprises a regulator controlled by the output voltage appearing between the positive and negative contact of the housing, for selectively applying power available at the respective terminals of the power cells to the contacts of the housing, said selective power application including a first capacitor coupled across the positive and negative contacts of the housing, and a second capacitor coupled across the positive and negative terminals of the power cell.

50. A battery pack according to claim 47, wherein the voltage converter comprises a selector, controlled by the output voltage appearing between the positive and negative contact of the housing, for selectively applying power available at the respective terminals of the power cells to the contacts of the housing, said selective power application including a first capacitor coupled across the positive and negative contacts of the housing, and a second capacitor coupled across the positive and negative terminals of the power cell.

51. A battery pack according to claim 46, wherein the housing comprises a frame for receiving the power cell elements, for supporting the voltage converter, and further including a circuit header board mounted within the housing, the circuit header including terminals and conductive extensions for electrically coupling the power cell elements to the voltage converter and for electrically coupling the converted voltage values to the external contacts of the housing.

52. A battery pack according to claim 46, wherein the voltage converter is a voltage converter module comprising a circuit board, and wherein said power application selector is mounted on said circuit board and further comprising a frame mounted on said circuit board and coupled to said power application selector for controlling the operation of the selector.

53. A battery pack according to claim 46, further comprising a switch for selectively isolating the positive terminal of the power cell from being coupled to the voltage converter.

54. A battery pack according to claim 47, further comprising charging contacts for coupling a battery charger across the positive and negative terminals of the power cell, whereby a voltage applied to the terminals of the power cell is applied to the voltage converter for conversion to values within said predetermined second range for application to said external contacts of the housing.

55. A battery pack according to claim 46, wherein the housing comprises a molded housing, said housing supporting the external negative contact disposed at a base of the housing and centered on a central axis through the housing and the external positive contact disposed in spaced relationship along said base adjacent a side wall of the housing, the housing further comprising a guide for receiving the voltage converter and the power cell elements, the housing further comprising a header for electrically coupling the power cell elements to the voltage converter and for electrically coupling the converted voltage values to the external contacts of the housing.

56. A battery pack according to claim 55, wherein the positive external contact is a first positive external contact, the housing further supporting a second positive external contact spaced from the centered negative contact in symmetry to said first positive external contact.

57. A battery pack according to claim 46, wherein the regulator comprises a converter for converting the positive voltage at the positive terminal with respect to the negative terminal of the power cell to a predetermined constant value over the discharge cycle of the power cell and for applying the converted voltage between the positive and negative external contacts.

58. A battery pack according to any of claims 46, which further comprises a power input terminal disposed in the housing and extending through the housing, an external portion of the power input terminal being adapted to be coupled to a positive power terminal of a battery charging device, the negative external contact being adapted to be coupled to the negative power terminal of the battery charging device, whereby a positive input voltage at a voltage level in excess of the voltage level of the power cell applied to the positive terminal with respect to the negative terminal of the power cell for charging the power cell is converted by the voltage converting prior to the voltage converter applying the voltage to the positive external contact of the battery pack.

59. A battery pack according to claim 58, wherein the housing has a predetermined width between two opposite side walls, a base extending between the two side walls, the external contact and the power input terminal being spacedly disposed along the base, wherein a first one of the external contacts is centered along the base between the two opposite side walls and a second one of the external contact is spacedly located at a first, predetermined distance from the first external contact adjacent one of the side walls, and the power input terminal is spacedly located at a second predetermined distance from the centered first terminal.

60. A battery pack according to claim 59, wherein the first one of the external contacts is the negative contact, the positive power terminal is a first positive power terminal and the external portion thereof is a first positive contact, the housing including a second positive power terminal extending through the housing, a portion of the second positive power terminal being disposed externally of the housing and forming a second positive contact, the second positive contact being spacedly located at the first predetermined distance from the negative external contact adjacent the other side wail of the housing, the second predetermined distance being less than the first predetermined distance such that the power input terminal is located between the negative and one of the positive contacts of the battery pack, the for converting the voltage and for applying the converted voltage including a connector for applying the converted voltage to the second positive external contact of the battery pack.

61. A battery pack according to claim 46, wherein the power cell is a plurality of power cell elements, the housing including a frame for slidably receiving the power cell elements, and wherein the switch for converting the voltage at the positive terminals of the power cell and for applying the converted voltage to the positive external contact includes a voltage converter module, the voltage converter module having negative and positive input terminals and negative and positive output terminals, and disposed within the housing adjacent a base of the housing for electrically coupling the power cell elements in series, thereby forming the power cell with the combined voltage of each of the power cell elements, for coupling the negative and the positive terminals of the power cell to the respective input terminals of the voltage converter module, and for coupling the output terminals of the voltage converter module to the respective external contact of the battery pack.

62. A battery pack according to claim 59, wherein the housing further includes a frame for slidably receiving the voltage converter module, a fastener for coupling, said fastener including a resilient connector disposed adjacent an inner end of the frame for slidably receiving the voltage converter module for coupling the inserted voltage converter module to the fastener, and wherein the battery pack further includes a cap adapted to retain the power cell elements and the voltage converter module within the housing, the cap including portions of the fastener for coupling the power cell elements in series.

63. A battery pack according to claim 46, wherein:

the regulator comprises a voltage converter module having negative and positive input and output terminals;

wherein

said housing has spaced side walls, a base, an open end opposite the base, and a frame for receiving and for retaining the plurality of power cell elements and the voltage converter module within the housing; and

further comprises

a coupler for coupling the plurality of power cell elements in series, thereby providing, a power cell having the combined voltage of the elements and negative and positive output terminals, a first terminal coupler for coupling the negative and positive output terminals of the power cell to respective negative and positive input terminals of the voltage converter module, and a second terminal coupler for coupling the negative and positive output terminals of the voltage converter module to the respective negative and positive power contacts of the housing.