Electrode for power storage device, power storage device, and manufacturing method of electrode for power storage device

Abstract

To improve the long-term cycle performance of a lithium-ion battery or a lithium-ion capacitor by minimizing the decomposition reaction of an electrolytic solution and the like as a side reaction of charge and discharge in the repeated charge and discharge cycles of the lithium-ion battery or the lithium-ion capacitor. A current collector and an active material layer over the current collector are included in an electrode for a power storage device. The active material layer includes a plurality of active material particles and silicon oxide. The surface of one of the active material particles has a region that is in contact with one of the other active material particles. The surface of the active material particle except the region is partly or entirely covered with the silicon oxide.

What is claimed is: 
     
         1 . An electrode for a power storage device, comprising:
 a current collector; and   an active material layer over the current collector, the active material layer comprising a plurality of active material particles and silicon oxide,   wherein a surface of one of the plurality of active material particles has a region that is in contact with another of the plurality of active material particles, and   wherein the surface of the one of the plurality of active material particles except the region is at least partly covered with the silicon oxide.   
     
     
         2 . The electrode for a power storage device, according to  claim 1 ,
 wherein the plurality of active material particles comprise a carbon material, and
 wherein an R value of the carbon material is less than 0.4. 
   
     
     
         3 . The electrode for a power storage device, according to  claim 1 ,
 wherein the plurality of active material particles comprise a carbon material, and
 wherein an R value of the carbon material is less than 1.1. 
   
     
     
         4 . The electrode for a power storage device, according to  claim 1 , further comprising a binder,
 wherein the binder is in contact with the plurality of active material particles and the silicon oxide.   
     
     
         5 . A power storage device comprising the electrode according to  claim 1 . 
     
     
         6 . An electrode for a power storage device, comprising:
 a current collector; and   an active material layer over the current collector, the active material layer comprising a plurality of active material particles and metal oxide,   wherein a surface of one of the plurality of active material particles has a region that is in contact with another of the plurality of active material particles, and   wherein the surface of the one of the plurality of active material particles except the region is at least partly covered with the metal oxide.   
     
     
         7 . The electrode for a power storage device, according to  claim 6 ,
 wherein the plurality of active material particles comprise a carbon material, and
 wherein an R value of the carbon material is less than 0.4. 
   
     
     
         8 . The electrode for a power storage device, according to  claim 6 ,
 wherein the plurality of active material particles comprise a carbon material, and
 wherein an R value of the carbon material is less than 1.1. 
   
     
     
         9 . The electrode for a power storage device, according to  claim 6 , further comprising a binder,
 wherein the binder is in contact with the plurality of active material particles and the metal oxide.   
     
     
         10 . A power storage device comprising the electrode according to  claim 6 .