Mechanical and thermal improvements in metal hydride batteries, battery modules, and battery packs

• US 20050058892A1
• Filed: 09/09/2004
• Published: 03/17/2005
• Est. Priority Date: 10/25/1993
• Status: Active Grant

• Current Assignee: Chevron Technology Ventures LLC (Chevron Corp.)
• Original Assignee: Chevron Technology Ventures LLC (Chevron Corp.)
• Inventors: Gow, Philippe, Ovshinsky, Stanford R., Corrigan, Dennis A., Holland, Arthur, Higley, Lin, Osgood, Anthony, Venkatesan, Srinivasan, Fillmore, Donn, Laming, Kenneth, Himmler, Ronald, Karditsas, Nick, Dhar, Subhash K.
• Granted Patent: US 7,217,473 B2
• Time in Patent Office: Days
• US Class Current: 429/120
• CPC Class Codes: H01M 10/345 Gastight metal hydride accumulators
• CPC Class Codes: H01M 10/443 in response to temperature
• CPC Class Codes: H01M 10/613 Cooling or keeping cold
• CPC Class Codes: H01M 10/617 for achieving uniformity or desired distribution of temperature
• CPC Class Codes: H01M 10/625 Vehicles
• CPC Class Codes: H01M 10/63 Control systems charging or discharging in response to temperature H01M10/44 , H01M10/443; measurement of temperature H01M10/48 , H01M10/486
• CPC Class Codes: H01M 10/635 based on ambient temperature
• CPC Class Codes: H01M 10/647 Prismatic or flat cells, e.g. pouch cells
• CPC Class Codes: H01M 10/651 characterised by parameters specified by a numeric value or mathematical formula, e.g. ratios, sizes or concentrations
• CPC Class Codes: H01M 10/652 characterised by gradients for achieving a desired temperature gradient H01M10/617
• CPC Class Codes: H01M 10/653 characterised by electrically insulating or thermally conductive materials
• CPC Class Codes: H01M 10/654 located inside the innermost case of the cells, e.g. mandrels, electrodes or electrolytes
• CPC Class Codes: H01M 10/655 Solid structures for heat exchange or heat conduction
• CPC Class Codes: H01M 10/6551 Surfaces specially adapted for heat dissipation or radiation, e.g. fins or coatings
• CPC Class Codes: H01M 10/6554 Rods or plates
• CPC Class Codes: H01M 10/6557 arranged between the cells
• CPC Class Codes: H01M 10/6562 with free flow by convection only
• CPC Class Codes: H01M 10/6563 with forced flow, e.g. by blowers
• CPC Class Codes: H01M 10/6567 Liquids
• CPC Class Codes: H01M 10/658 by thermal insulation or shielding
• CPC Class Codes: H01M 50/209 : adapted for prismatic or rectangular cells H01M50/216 takes precedence
• CPC Class Codes: H01M 50/30 : Arrangements for facilitating escape of gases
• CPC Class Codes: H01M 50/317 : Re-sealable arrangements
• CPC Class Codes: H01M 50/55 : on the same side of the cell
• CPC Class Codes: H01M 50/553 : Terminals adapted for prismatic, pouch or rectangular cells
• CPC Class Codes: H01M 50/562 : characterised by the material
• CPC Class Codes: H01M 50/566 : by welding, soldering or brazing
• CPC Class Codes: Y02E 60/10 : Energy storage using batteries
• CPC Class Codes: Y10T 29/4911 : including sealing

Abstract

Mechanically and thermally improved rechargeable batteries, modules and fluid-cooled battery pack systems. The battery is prismatic in shape with an optimized thickness to width to height aspect ratio which provides the battery with balanced optimal properties when compared with prismatic batteries lacking this optimized aspect ratio. The optimized thickness, width and height allow for maximum capacity and power output, while eliminating deleterious side affects. The battery case design allows for unidirectional expansion which is readily compensated for by applying external mechanical compression counter to that direction. In the module, the batteries are bound within a module bundling/compression means under external mechanical compression which is optimized to balance outward pressure due to expansion and provide additional inward compression to reduce the distance between the positive and negative electrodes, thereby increasing overall battery power. The fluid-cooled battery pack includes; 1) a battery-pack case having coolant inlet and outlet; 2) battery modules within the case such that the battery module is spaced from the case walls and from other battery modules to form coolant flow channels along at least one surface of the bundled batteries; and 3) at least one coolant transport means. The width of the coolant flow channels allows for maximum heat transfer. Finally the batteries, modules and packs can also include means for providing variable thermal insulation to at least that portion of the rechargeable battery system which is most directly exposed to said ambient thermal condition, so as to maintain the temperature of the rechargeable battery system within the desired operating range thereof under variable ambient conditions.

Claims

1. A fluid cooled battery pack for a vehicle drive system, said battery pack comprising:

a battery pack case, said case including at least one coolant inlet and at least one coolant outlet;

a plurality of battery modules disposed within and arranged in a matrix configuration within said case, each of said battery modules including a plurality of battery cells, said battery modules positioned within said case such that said battery modules are spacedly disposed from other battery modules to form intermodular gaps between said modules, said intermodule gaps providing coolant flow channels between said battery modules;

at least one coolant transport means, said coolant transport means causing said coolant to enter said coolant inlet of said case, to flow through said coolant flow channels and to exit said coolant outlet; and

wherein the coolant flow channels are sized within a range such that narrowing the intermodule gap between modules results in decreasing cooling fluid volumetric flow while increasing cooling fluid velocity and within a range to maintain a temperature difference between said battery modules of 8°

C. or less while holding the maximum temperature of said battery modules to 65°

C. or below in a wide variety of operating conditions.

2. The fluid cooled battery pack of claim 1, wherein said coolant flow channels impede the flow of coolant flow by 5 to 30% in flow volume.

3. The fluid cooled battery pack of claim 1, wherein said battery cells have a nickel metal hydride chemistry.

4. The fluid cooled battery pack of claim 1, wherein said modules are arranged in the battery pack case to provide fro coolant flow along a vertical direction of said battery modules.

5. The fluid cooled battery pack of claim 1, wherein said battery cells of the same battery module do not have significant coolant flow between them.

6. The fluid cooled battery pack of claim 1, wherein module spacers are interposed between opposite battery modules in the battery pack case.

7. The fluid cooled battery pack of claim 1, wherein the width of the coolant flow channels between modules is from 0.3 to 12 mm.

8. The fluid cooled battery pack of claim 1, wherein the width of the coolant flow channels between modules is from 1 to 9 mm.

9. The fluid cooled battery pack of claim 1, wherein the plurality of battery modules disposed within and arranged in the matrix configuration are arranged to allow coolant flow directly across at least one surface of said bundled batteries.