Energy secondary lithium-metal batteries

Secondary lithium-metal batteries which have a lithium-metal anode are attractive because their energy density is theoretically higher than that of lithium-ion batteries. Lithium-molybdenum disulfide batteries were the world s first secondary cylindrical lithium—metal batteries. However, the batteries were recalled in 1989 because of an overheating defect. Lithium-manganese dioxide batteries are the only secondary cylindrical lithium—metal batteries which are manufactured at present. Lithium-vanadium oxide batteries are being researched and developed. Furthermore, electrolytes, electrolyte additives and lithium surface treatments are being studied to improve safety and recharge-ability. 

In contrast to primary batteries, a secondary, or rechargeable, battery is recharged when it runs down by supplying electrical energy to reverse the cell reaction and re-form reactant. In other words, in this type of battery, the voltaic cells are periodically converted to electrolytic cells to restore nonequilibrium concentrations of the cell components. By far the most widely used secondary battery is the common car battery. Two newer types are the nickel-metal hydride battery and the lithium-ion battery. 

Lithium-Ion Batteries, Fig, 2 Specific energy and energy density of secondary batteries. Ni-Cd nickel-cadmium battery, Ni-MH nickel-metal hydride battery, LIB lithium ion battery... 

From Table 3.1, Li-air secondary batteries may be particularly attractive due to their high theoretical energy density which mainly results from the light weight of lithium metal. 

To improve the safety of secondary lithium batteries, the metallic lithium is replaced by another intercalation compound such as graphite. In addition, the cathode would contain ionic lithium in its structure, which is intercalated in the anode or the cathode depending on the direction of the current. Lithium-ion cells are the most advanced batteries now in the market. These cells supply up to 4 volts, have an energy density close to 120 Wh/kg, and have a long life at room temperature. The technology is based on the use of appropriate lithium intercalation compounds as electrodes. Normally a lithium transition metal oxide is used as the cathode and carbonaceous materials serve as the anode. 

---