An inorganic membrane as a separator for lithium-ion battery

An Al(2)O(3) inorganic separator is prepared by a double sintering process. The Al(2)O(3) separator has a high porosity and good mechanical strength. After the liquid electrolyte is infiltrated, the separator exhibits quite high ionic conductivities, and even the conductivity reaches 0.78 mScm(-1) at 20 degrees C. Furthermore, the inorganic separator has an advantage over the polymer separator in the electrolyte retention. The LiFePO(4)/graphite cell using the Al(2)O(3) inorganic separator shows higher discharge capacity and rate capability, and better low-temperature performance than that using the commercial polymer separator, which indicates that the Al(2)O(3) separator is very promising to be applied in the lithium-ion batteries. (C) 2011 Elsevier B.V. All rights reserved.