POUCH CONTAINMENT SYSTEM FOR THERMAL PROTECTION USING HEAT CAPACITY ADDITIVES
This disclosure describes a battery device with at least two battery cells and a stainless-steel foil pouch located between the battery cells. The stainless-steel foil pouch holds a liquid and heat capacity additives that prevent and/or delay thermal propagation.
1 . A battery protection system, comprising:
a sealed chamber configured to be positioned between adjacent battery cells, wherein:
the sealed chamber is filled with a heat-absorbing fluid comprising water and one or more heat capacity additives selected to delay thermal propagation between the battery cells,
the heat-absorbing fluid comprises from 20 wt % to 60 wt % water and from 40 wt % to 80 wt % of the one or more heat capacity additives, and
the heat capacity additives increase a specific heat capacity of the fluid relative to water alone.
2 . The battery protection system of claim 1 , wherein the heat capacity additive comprises lithium carbonate and/or lithium fluoride.
3 . The battery protection system of claim 1 , wherein the heat-absorbing fluid comprises ceramic beads or spheres suspended within a medium.
4 . The battery protection system of claim 1 , wherein the heat-absorbing fluid comprises suspended solids selected from aluminum oxide, silica, magnesium hydroxide, aluminum hydroxide, lithium hydroxide, graphite, expanded graphite, expandable graphite soft/hard carbon and magnesium oxide.
5 . The battery protection system of claim 1 , wherein the heat-absorbing fluid comprises a thickener to maintain a uniform suspension of the heat capacity additives.
6 . The battery protection system of claim 1 , wherein the sealed chamber is formed by metal sheets welded together to contain the heat-absorbing fluid.
7 . The battery protection system of claim 1 , wherein the sealed chamber is integrated at least one of the submodule, module, or pack level.
8 . The battery protection system of claim 1 , wherein the heat-absorbing fluid is configured to remain in a sub-boiling state under normal battery operating conditions below 80° C.
9 . The battery protection system of claim 1 , wherein the heat capacity additive comprises baking soda.
10 . The battery protection system of claim 1 , wherein the sealed chamber comprises multiple physically connected but fluidically isolated sub-chambers that are separately sealed and individually fillable for independent inflation.
11 - 20 . (canceled)