High Power Lithium Ion Battery Facilitated by an Advanced Cathode 2008-01-2866
This paper presents the test results from cells fabricated using an advanced NMC cathode incorporated into the Electro Energy wafer cell which will increase the specific energy and specific power of the completed battery. The NMC material is processed to produce a cathode with loading and porosity which will result in an electrolyte interface capable of high ionic conduction. In addition electron conductivity is enhanced by a unique coating process which provides intimate contact between the NMC and the aluminum current collector. Many cells were fabricated to determine the optimum electrode and cell parameters to optimize the energy density, specific energy, power density and specific power of the cells. Cells were subjected to rate versus temperature discharge test regimes to determine capacity at various temperatures and rates from C/2 to 40C. Test results show a high energy lithium ion battery can be fabricated using Electro Energy wafer cells which will have a specific energy greater 200 Wh/kg and capable of greater than the C-rate. High power cells give greater than 120 Wh/kg and are capable of 2.5 KW/kg during continuous discharge at moderate temperatures. In addition, the battery is capable of much higher specific power than typical lithium ion batteries in use today. The battery design allows for increased discharge efficiency at high rates, compact packaging, and low manufacturing costs which will make available batteries capable of meeting DoD requirements of fast recharge, high temperature performance, higher energy density, cost effectiveness and safety in lithium ion batteries.