Theoretical energy density above 1000 Wh kg −1 /800 Wh L −1 and electromotive force over 1.5 V are taken as the screening criteria to reveal significant battery systems for the next-generation energy storage. Practical energy densities of the cells are estimated using a solid-state pouch cell with electrolyte of PEO/LiTFSI.
As a result, the intercalation battery is more realistic to achieve high energy densities in the near term. Though enormous challenges remain, the conversion battery is the long-term pursuing target for high energy densities because it has a higher theoretical limit. 7.2. Reactions in primary batteries
Energy density of batteries experienced significant boost thanks to the successful commercialization of lithium-ion batteries (LIB) in the 1990s. Energy densities of LIB increase at a rate less than 3% in the last 25 years . Practically, the energy densities of 240–250 Wh kg −1 and 550-600 Wh L −1 have been achieved for power batteries.
The rechargeable battery systems with lithium anodes offer the most promising theoretical energy density due to the relatively small elemental weight and the larger Gibbs free energy, such as Li–S (2654 Wh kg −1), Li–O 2 (5216.9 Wh kg −1), Li–V 2 O 5 (1532.6 Wh kg −1), Li–FeF 3 (1644 Wh kg −1), etc. Fig. 1. The superiority of lithium metal anode.
These efforts resulted in the successful realization of reversible charge and discharge in the ultra-high energy density battery.
High-energy-density batteries are the eternal pursuit when casting a look back at history. Energy density of batteries experienced significant boost thanks to the successful commercialization of lithium-ion batteries (LIB) in the 1990s. Energy densities of LIB increase at a rate less than 3% in the last 25 years .