The formation mechanism of protective interphases on high voltage cathodes of lithium ion batteries, resulting from phenyl trifluoromethyl sulfide (PTS) as an electrolyte additive, is understood through theoretical calculations, and confirmed by evaluating the cyclic stability of a lithium-rich cathode, Li_1·2Mn_0·54Ni_0·13Co_0·13O₂, in the electrolytes with and without PTS. It is found that PTS is oxidized through the transferring of one fluorine atom from methyl to phenyl and the subsequent breaking of bond S–C in phenyl, yielding fluorobenzene and sulfur-contained radical that construct mainly the protective interphase. With this interphase formed from PTS, the cyclic stability of Li_1·2Mn_0·54Ni_0·13Co_0·13O₂ is significantly improved. The capacity retention of Li_1·2Mn_0·54Ni_0·13Co_0·13O₂ in 1.0 M LiPF₆-EC/EMC/DEC (3/5/2 by weight) at 0.5C after 200 cycles is enhanced from 39% to 83% by adding 0.5% PTS.

通过理论计算可以理解由苯基三氟甲基硫醚（PTS）作为电解质添加剂在锂离子电池高压阴极上形成保护性相的机理，并通过评估富锂阴极Li ₁的循环稳定性来证实带和不带PTS的电解液中的_·2 Mn _0·54 Ni _0·13 Co _0·13 O ₂。结果发现，PTS通过一个氟原子从甲基转移到苯基，然后在苯基中断裂S–C键而被氧化，生成氟苯和含硫自由基，主要构成保护性相间相。在由PTS形成的该相间，Li _1·2的循环稳定性Mn _0·54 Ni _0·13 Co _0·13 O ₂显着改善。增强200次循环后，在0.5C下1.0 M LiPF ₆ -EC / EMC / DEC（3/5/2重量比）中Li _1·2 Mn _0·54 Ni _0·13 Co _0·13 O ₂的容量保持率从39％增至83％，添加0.5％的PTS。