ANISOTROPIC EXPANSION OF SILICON-DOMINANT ANODES
Systems and methods for anisotropic expansion of silicon-dominant anodes may include forming an anode by pyrolyzing an active material layer comprising a binder and silicon particles in a temperature range of 600 to 800° C.; and forming a battery cell comprising a cathode, an electrolyte, and the anode, where the anode comprises the pyrolyzed active material layer on a current collector. A lateral expansion of the anode during operation may be less than 2%, less than 1%, or less than 0.6%. The active material layer may be pyrolyzed on the current collector or may be pyrolyzed on a substrate before laminating on the current collector. The anode active material layer may be pyrolyzed using a 1 hour dwell time or less or using a 2 hour dwell time or less. The active material layer may be pyrolyzed in a temperature range of 650 to 800° C.
1 . A method of forming a battery cell, the method comprising:
forming an anode by pyrolyzing an active material layer comprising a binder and silicon particles in a temperature range of 600 to 800° C.;
forming a battery cell comprising a cathode, an electrolyte, and the anode, the anode comprising the pyrolyzed active material layer on a current collector, wherein a lateral expansion of the anode during operation is less than 2%.
2 . The method according to claim 1 , wherein the lateral expansion of the anode during operation is less than 1%.
3 . The method according to claim 1 , wherein the lateral expansion of the anode during operation is less than 0.6%.
4 . The method according to claim 1 , comprising pyrolyzing the active material layer on the current collector.
5 . The method according to claim 1 , comprising pyrolyzing the active material layer on a substrate before laminating on the current collector.
6 . The method according to claim 1 , comprising pyrolyzing the anode active material layer using a 1 hour dwell time or less.
7 . The method according to claim 1 , comprising pyrolyzing the anode active material layer using a 2 hour dwell time or less.
8 . The method according to claim 1 , comprising pyrolyzing the active material layer in a temperature range of 650 to 800° C.
9 . The method according to claim 1 , wherein the current collector comprises copper.
10 . A method of forming a battery cell, the method comprising:
forming an anode by pyrolyzing an active material layer comprising a binder and silicon particles in a temperature range of 650 to 800° C.;
forming a battery cell comprising a cathode, an electrolyte, and the anode, the anode comprising the pyrolyzed active material layer on a copper current collector, wherein a lateral expansion of the anode during operation is less than 1%.