PLA Developing Lithium-ion Powered Submarines

China is developing submarines powered by a lithium-ion battery propulsion system as they offer higher energy density and longer dive times than old diesel submarines.

Chinese researchers see them as the "wave of the future," Andrew Erickson, a professor at the Naval War College in Newport, Rhode Island was quoted as saying by Diplomat, Tokyo-based news magazine on May 28.

The PLA Navy is discussing putting lithium-ion batteries "on a new generation of conventional subs sometime between now and 2020, but there is no indicator as yet of the type of submarine that might be," Erickson added.

China is struggling to advance its submarine technology as it is lagging behind, when compared to west. The PLA's Type 095 nuclear submarine’s major structural weaknesses is the lack of propulsion engineering because most engines used in Chinese submarines are either based on imported foreign technology or built domestically under license.

The PLA needs submarines with reactors that are "efficient, long-lasting, reliable and quiet enough," Erickson said. He also added that it is the reason for China to equip them in their Song- and Yuan-class attack submarines.

Diesel submarines are stealthier than nuclear submarines because the former are specifically designed to minimize vibration and noise in order to evade sonar detection. However, China finds longer-lasting lithium-ion batteries could be the solution as it does not require submarines to come to the surface for recharging batteries.

The PLA Navy currently has five nuclear attack submarines, four nuclear ballistic missile submarines and 53 diesel attack submarines, the Pentagon's Office of Naval Intelligence said.

The Pentagon estimates that by 2020 China's underwater force will grow between 69 and 78 submarines.