Battery maintenance device with thermal buffer

Patent metadata

Field	Value
Publication number	US-9419311-B2
Application number	US-81829010-A
Country	US
Kind code	B2
Filing date	Jun 18, 2010
Priority date	Jun 18, 2010
Publication date	Aug 16, 2016
Grant date	Aug 16, 2016

Abstract

A battery maintenance device configured to maintain a storage battery. An electrical connection couples the battery maintenance device to the storage battery. Maintenance circuitry couples to the battery through the electrical connection and performs maintenance on the battery. The maintenance circuitry includes an electrical load configured to draw an electrical current from the battery. The electrical current causes the electrical load to heat. A phase change material is thermally coupled to the load. The phase change material has a specific heat index which has a non-linear relationship to temperature to thereby reduce a rate of change in temperature of the electrical load.

First claim

What is claimed is:

1. A battery maintenance device configured to maintain a storage battery, comprising:
an electrical connection configured to couple to a storage battery;
maintenance circuitry located externally to the battery configured to couple to the battery through the electrical connection and perform maintenance on the battery, the maintenance circuitry including an electrical load comprising at least one resistor configured to draw an electrical current from the storage battery, the electrical current causing the electrical load to heat; and
a container comprising:
a lower enclosure having a cavity that includes a phase change material, the phase change material having a specific heat index which has a non-linear relationship to temperature; and
a top cover having an outer side and an inner side, which faces the cavity of the lower enclosure;

wherein:
the at least one resistor is attached to the inner side of the top cover and includes fins in direct physical contact with the phase change material; and
the maintenance circuitry comprises battery test circuitry configured to perform a battery test based upon current drawn from the battery by the load.

2. The battery maintenance device of claim 1 wherein the battery test comprises a load test.

3. The battery maintenance device of claim 1 wherein the battery test is based upon a dynamic parameter generated using the electrical load.

4. The battery maintenance device of claim 1 wherein the phase change material comprises paraffin wax.

5. The battery maintenance device of claim 1 wherein the electrical connection to the battery comprises a Kelvin connection.

6. The battery maintenance device of claim 1 wherein the maintenance circuitry comprises a battery charger.

7. The battery maintenance device of claim 1 wherein the phase change material transitions from a solid to a liquid during heating caused by heat from the electrical load.

8. A method for maintaining a storage battery, comprising:
electrically connecting battery maintenance circuitry to the storage battery, wherein:
the battery maintenance circuitry is external to the battery;
the maintenance circuitry includes a container comprising a lower enclosure having a cavity that includes a phase change material having a specific heat index which has a non-linear relationship to temperature, and a top cover having an outer side and an inner side, which faces the cavity of the lower enclosure; and
the maintenance circuitry including an electrical load comprising at least one resistor that is attached to an inner side of the top cover and includes fins in direct physical contact with the phase change material;
performing maintenance on the storage battery using the battery maintenance circuitry and drawing an electrical current from the storage battery through the at least one resistor;
coupling heat generated by the electrical load directly to the phase change material, thereby reducing a rate of change in temperature of the electrical load; and
performing a battery test using battery test circuitry based upon current drawn from the battery by the electrical load.

9. The method of claim 8 wherein the battery test comprises a load test.

10. The method of claim 8 wherein the battery test includes measuring a dynamic parameter generated using a forcing function provided by the electrical load.

11. The method of claim 8 wherein the phase change material comprises paraffin wax.

12. The method of claim 8 wherein the electrical connection to a battery comprises a Kelvin connection.

13. The method of claim 8 wherein the battery maintenance circuitry comprises a battery charger.

14. The method of claim 8 wherein the phase change material transitions from a solid to a liquid during heating.

Assignees

• Bertness Kevin I
• Midtronics Inc

Inventors

• Bertness Kevin I

Classifications

• H02J7/54

  Passive balancing, e.g. using resistors or parallel MOSFETs · CPC title

• H01M10/48

  Accumulators combined with arrangements for measuring, testing or indicating the condition of cells, e.g. the level or density of the electrolyte (constructional details of current conducting connections for detecting conditions inside cells or batteries, e.g. details of voltage sensing terminals, H01M50/569) · CPC title

• H02J7/0016

  Electricity · mapped topic

• H01M10/4285 Primary

  Testing apparatus · CPC title

• Y02T10/7055

  Cross-Sectional Technologies · mapped topic