Electrode with integrated ceramic separator

Abstract

An electrode including an integrated separator for use in an electrochemical device may include one or more active material layers, and a separator layer comprising inorganic particles. An interlocking region may couple the separator layer to an adjacent active material layer. In some examples, the interlocking region may include interlocking fingers formed by an interpenetration of active material particles of the active material layers with ceramic particles of the separator.

What is claimed is: 
     
         1 . A method of manufacturing an electrode including an integrated separator layer, the method comprising:
 causing relative motion between an active material composite dispenser and a current collector substrate on which is disposed a first layer of active material composite, wherein the first layer includes a plurality of first active material particles and a first binder, the first active material particles having a first average particle size and a first viscosity; and   applying a separator layer to the first layer of active material composite, using an orifice of the dispenser, the separator layer including a separator composite slurry having a plurality of ceramic particles and a second binder, the ceramic particles having a second average particle size;   wherein applying the separator layer forms an interphase layer adhering the separator layer to the first layer of active material composite, the interphase layer including an interpenetration of the first layer and the separator layer in which first fingers of the first layer interlock with second fingers of the separator layer.   
     
     
         2 . The method of  claim 1 , wherein the interphase layer has a third average particle size between the first average particle size and the second average particle size. 
     
     
         3 . The method of  claim 1 , wherein causing the relative motion comprises moving the current collector substrate using a backing roll. 
     
     
         4 . The method of  claim 1 , wherein the dispenser comprises a slot die coating head, and the orifice is a slot of the coating head. 
     
     
         5 . The method of  claim 1 , wherein the ceramic particles comprise alumina. 
     
     
         6 . The method of  claim 1 , further comprising:
 calendering the electrode by pressing the first layer and the separator layer against the current collector substrate using a roller, wherein the separator layer is configured to transfer a load applied to the separator layer by the roller to the first layer.   
     
     
         7 . The method of  claim 6 , wherein the electrode includes exactly one crust layer. 
     
     
         8 . The method of  claim 1 , wherein a boundary between the first layer and the separator layer has a surface area greater than a planar cross-section taken parallel to the current collector substrate. 
     
     
         9 . A method of manufacturing an electrode including an integrated separator layer, the method comprising:
 causing a current collector substrate and an active material composite dispenser to move relative to each other, wherein the current collector substrate is at least partially coated by an uncalendered first layer of active material composite including a plurality of first active material particles and a first binder, the first active material particles having a first average particle size; and   coating at least a portion of the first layer with a second layer of separator material slurry, using an orifice of the dispenser, wherein the second layer includes a plurality of ceramic particles and a second binder, the ceramic particles having a second average particle size; and   forming an interlocking region adhering the second layer to the first layer, the interlocking region including an interpenetration of the first layer and the second layer in which first fingers of the first layer interlock with second fingers of the second layer.   
     
     
         10 . The method of  claim 9 , wherein the interlocking region has a third average particle size between the first average particle size and the second average particle size. 
     
     
         11 . The method of  claim 9 , wherein causing the current collector substrate and the dispenser to move relative to each other comprises moving the substrate using a backing roll. 
     
     
         12 . The method of  claim 9 , wherein the dispenser comprises a slot die coating head, such that the orifice is a slot of the coating head. 
     
     
         13 . The method of  claim 9 , further comprising:
 calendering the electrode by pressing the combined first and second layers against the current collector substrate using a roller, wherein the second layer is configured to transfer a load applied to the second layer by the roller to the first layer.   
     
     
         14 . A method of manufacturing an electrode including an integrated separator layer, the method comprising:
 applying an active material composite to a foil substrate, wherein the first active material composite comprises a plurality of first active material particles and a first binder, the first active material particles having a first average particle size; and   applying a separator material composite to the active material composite before calendering, using a slot of a slot-die coating head dispenser, wherein the separator material composite comprises a plurality of inorganic particles and a second binder, the inorganic particles having a second average particle size;   wherein an interpenetrating boundary layer is formed between the active material composite and the separator composite.   
     
     
         15 . The method of  claim 14 , further comprising causing the foil substrate and the slot of the slot-die coating head dispenser to move relative to each other. 
     
     
         16 . The method of  claim 14 , wherein the slot-die coating head dispenser comprises a single chamber slot-die coating head. 
     
     
         17 . The method of  claim 14 , wherein the inorganic particles comprise alumina. 
     
     
         18 . The method of  claim 14 , further comprising:
 calendering the electrode by pressing the combined active material composite and separator material composite against the foil substrate using one or more rollers, wherein the separator material composite has a higher tolerance to bulk compression than the active material composite and is configured to transfer a load applied to the separator composite by the one or more rollers to the first layer.   
     
     
         19 . The method of  claim 18 , wherein the electrode includes exactly one crust layer. 
     
     
         20 . The method of  claim 14 , wherein the active material composite comprises:
 a first active material layer comprising the plurality of first active material particles and the first binder; and   a second active material layer comprising a plurality of second active material particles and a third binder.