| 摘要 |
A multilayer electrode suitable for use in a secondary battery comprises, in sequence, a conductive layer 201, a first composite electrode layer 203a and a second composite electrode layer 203b. Each composite electrode layer comprises a particulate material suitable for use as the active material in a metal ion battery and a binder, wherein a major component of the active material of the first composite electrode layer is a material that is different from a material forming a major component of the active material of the second composite electrode layer. Preferably the binders of the first and second composite layers are also different, with the binder of the first layer being an elastomeric polymer (e.g. PVDF) and the binder of the second layer being a non-elastomeric polymer (e.g. PAA or a salt thereof). In a preferred example the major active component of the first layer is active carbon (e.g. graphite, graphene), and the major active component of the second layer is doped or undoped silicon. The use of layered electrodes improves both the capacity retention and cycle life of batteries including such layered electrodes. Preferably, the multilayer electrode is an anode for a metal ion battery, with the battery also including an electrolyte 205, a cathode layer 207 and a conductive metal layer 209. |
