abstract |
Electrode assemblies for use in electrochemical cells are provided. The negative electrode assembly includes negative electrode active material and an electrolyte chosen specifically for its useful properties in the negative electrode. Such properties include reductive stability and ability to accommodate expansion and contraction of the negative electrode active material. Similarly, the positive electrode assembly includes positive electrode active material and an electrolyte chosen specifically for its useful properties in the positive electrode. These properties include oxidative stability and the ability to prevent dissolution of transition metals used in the positive electrode active material. A third electrolyte can be used as separator between the negative electrode and the positive electrode. A cell is constructed with a cathode that includes a fluorinated electrolyte which does not penetrate into the solid-state polymer electrolyte separator between it and the lithium-based anode. Such an assembly improves charge transport properties without compromising the strength and durability of the separator. |