Lithium ion battery with thermal runaway protection
Lithium ion batteries are provided that include materials that provide advantageous endothermic functionalities contributing to the safety and stability of the batteries. The endothermic materials may include a ceramic matrix incorporating an inorganic gas-generating endothermic material. If the temperature of the lithium ion battery rises above a predetermined level, the endothermic materials serve to provide one or more functions to prevent and/or minimize the potential for thermal runaway, e.g., thermal insulation (particularly at high temperatures); (ii) energy absorption; (iii) venting of gases produced, in whole or in part, from endothermic reaction(s) associated with the endothermic materials, (iv) raising total pressure within the battery structure; (v) removal of absorbed heat from the battery system via venting of gases produced during the endothermic reaction(s) associated with the endothermic materials, and/or (vi) dilution of toxic gases (if present) and their safe expulsion from the battery system.
1. A multi-core lithium ion battery, comprising:
a sealed enclosure, including a lithium ion cell region and a shared atmosphere region in the interior of the enclosure;
a support member disposed within the lithium ion cell region of the sealed enclosure, the support member including a plurality of cavities, each cavity having an end open to the shared atmosphere region;
a plurality of lithium ion core members, each core member having an anode and a cathode that (i) are exposed to the shared atmosphere region through an open end of the core member and (ii) communicate with the shared atmosphere region by way of the open end of the cavity, wherein each of the core members is disposed within a corresponding one of the plurality of cavities, wherein said core members are substantially surrounded by a cavity wall along their lengths; and
one or more endothermic materials positioned in proximity to the lithium ion cell region.
2. The lithium ion battery of claim 1 , wherein at least one of the one or more endothermic materials is included within a ceramic matrix.
3. The lithium ion battery of claim 1 , wherein the one or more endothermic materials is capable of providing thermal insulation properties at and above an upper normal operating temperature associated with the proximate one or more lithium ion core members.
4. The lithium ion battery of claim 3 , wherein the one or more endothermic materials is selected to undergo one or more endothermic reactions between the upper normal operating temperature and a higher threshold temperature above which the lithium ion core member is liable to thermal runaway.
5. The lithium ion battery of claim 1 , wherein an endothermic reaction associated with at least one of the one or more endothermic materials results in evolution of gas.
6. The lithium ion battery of claim 5 , wherein at least one of the one or more endothermic materials is included within a ceramic matrix, and wherein the ceramic matrix has sufficient porosity to permit said gas to vent and thereby remove heat therefrom.
7. The lithium ion battery of claim 2 , wherein the ratio of ceramic matrix to endothermic material is in the range 1:9 to 9:1 by weight.
8. The lithium ion battery of claim 2 , wherein the ceramic matrix comprises one or more inorganic fibers, inorganic particulate materials and binders.
9. The lithium ion battery of claim 8 , wherein the inorganic particulate materials are selected from the group consisting of fumed ceramics, opacifiers, and mixtures thereof.
10. The lithium ion battery of claim 2 , wherein the ceramic mixture comprises 0-60 wt % ceramic oxide powder, 0-30 wt % opacifier, 10-90 wt % endothermic materials, 0-10 wt % dry binder, 0-60 wt % liquid binder, and 0-60 wt % fiber.
11. The lithium ion battery of claim 2 , wherein the ceramic matrix defines a gradient of the one or more endothermic materials.
12. The lithium ion battery of claim 2 , wherein the ceramic matrix defines a surface region having a higher concentration of the one or more endothermic materials as compared to at least one region within the ceramic matrix.
13. The lithium ion battery of claim 1 , wherein the one or more endothermic materials are formed into a shaped body that defines at least one recess configured and dimensioned to receive the support member.
14. The lithium ion battery of claim 13 , wherein the shaped body defines a plurality of recesses each configured and dimensioned to receive a support member.
15. The lithium ion battery of claim 2 , wherein the one or more endothermic materials are selected from the group consisting of
Approximate onset
of Decomposition
Mineral
Chemical Formula
(° C.)
Nesquehonite
MgCO 3 •3H 2 O
70-100
Gypsum
CaSO 4 •2H 2 O
60-130
Magnesium phosphate
Mg 3 (PO 4 ) 2 •8H 2 O
140-150
octahydrate
Aluminium hydroxide
Al(OH) 3
180-200
Hydromagnesite
Mg 5 (CO 3 ) 4 (OH) 2 •4H 2 O
220-240
Dawsonite
NaAl(OH) 2 CO 3
240-260
Magnesium hydroxide
Mg(OH) 2
300-320
Magnesium carbonate
MgO•CO 2(0.96) H 2 O (0.3)
340-350
subhydrate
Boehmite
AlO(OH)
340-350
Calcium hydroxide
Ca(OH) 2
430-450
wherein the “approximate onset of decomposition” is the temperature at which an endothermic reaction of the endothermic material is expected to begin.
16. The lithium ion battery of claim 2 , wherein the one or more endothermic materials includes sodium bicarbonate.
17. The lithium ion battery of claim 1 , wherein the one or more endothermic materials includes a first endothermic material characterized by a first approximate onset temperature for initiation of an endothermic reaction, and a second endothermic material characterized by a second approximate onset temperature for initiation of an endothermic reaction, and wherein the first approximate onset temperature is different than the second approximate onset temperature.
18. The lithium ion battery of claim 1 , wherein the sealed enclosure includes at least one vent.
19. The lithium ion battery of claim 18 , wherein the at least one vent is actuated in response to the pressure within the sealed enclosure exceeding a predetermined threshold pressure level.
20. The lithium ion battery of claim 18 , further comprising a flame arrestor in proximity to the at least one vent.
21. The lithium ion battery of claim 19 , wherein the predetermined threshold pressure level is between about 15 psi and 200 psi.
22. The lithium ion battery of claim 1 , wherein the one or more endothermic materials is selected from the group consisting of materials that include hydroxyl components, hydrous components, hydroxyl or hydrous components in combination with at least one carbonate, hydroxyl or hydrous components in combination with at least one sulphate, non-hydrous carbonates, non-hydrous sulphates, non-hydrous phosphates and combinations thereof.