US 12,087,913 B2
Three-dimensional batteries using constraint adhesive
Robert Keith Rosen, Rocklin, CA (US); Bruno A. Valdes, Sunnyvale, CA (US); Murali Ramasubramanian, Fremont, CA (US); and Robert S. Busacca, San Francisco, CA (US)
Assigned to Enovix Corporation, Fremont, CA (US)
Filed by Enovix Corporation, Fremont, CA (US)
Filed on Oct. 27, 2022, as Appl. No. 17/974,923.
Application 17/974,923 is a continuation of application No. PCT/US2022/022437, filed on Mar. 30, 2022.
Claims priority of provisional application 63/168,742, filed on Mar. 31, 2021.
Prior Publication US 2023/0057582 A1, Feb. 23, 2023
Int. Cl. H01M 50/474 (2021.01); H01M 4/04 (2006.01); H01M 10/0525 (2010.01); H01M 10/0585 (2010.01); H01M 50/403 (2021.01); H01M 50/46 (2021.01)
CPC H01M 10/0585 (2013.01) [H01M 4/0485 (2013.01); H01M 10/0525 (2013.01); H01M 50/403 (2021.01); H01M 50/46 (2021.01); H01M 50/474 (2021.01)] 19 Claims
OG exemplary drawing
 
1. An electrode assembly for a secondary battery comprising a population of unit cells, a constraint system, and an adhesive, wherein
the electrode assembly has mutually perpendicular longitudinal, transverse, and vertical axes, a first longitudinal end surface and a second longitudinal end surface separated from each other in a longitudinal direction, and a lateral surface surrounding an electrode assembly longitudinal axis AEA and connecting the first and second longitudinal end surfaces, the lateral surface having opposing first and second regions on opposite sides of the longitudinal axis and separated in a first direction that is orthogonal to the longitudinal axis, the electrode assembly having a maximum width WEA measured in the longitudinal direction, a maximum length LEA bounded by the lateral surface and measured in a transverse direction, and a maximum height HEA bounded by the lateral surface and measured in a vertical direction,
the electrode assembly further comprises a population of electrode structures, a population of counter-electrode structures, and an electrically insulating separator material electrically separating members of the electrode and counter-electrode populations, the members of the electrode and counter-electrode structure populations having opposing upper and lower end surfaces separated in the vertical direction, and wherein each member of the unit cell population comprises an electrode structure, a counter-electrode structure, and an electrically insulating separator between the electrode and counter-electrode structures,
the constraint system comprises (i) first and second primary growth constraints separated in the longitudinal direction, (ii) first and second connecting members separated in the vertical direction that connect the first and second primary growth constraints, and a subset of the members of the electrode or counter-electrode population wherein the first and second connecting members have opposing upper and lower inner surfaces to which the upper and lower end surfaces of the subset are adhered, respectively, by an electrically-insulating, thermoplastic, hot-melt adhesive, wherein:
the adhesive comprises a plurality of strips;
a first strip of the plurality of strips partially covers the upper inner surface of the first connecting member;
a second strip of the plurality of strips partially covers the lower inner surface of the second connecting member; and
the adhesive has (i) a melting temperature in a range of 75° C. to 130° ° C., and (ii) a melt index value as measured according to ASTM D1238 in a range of at least 20 to no more than 350.