Interfacial Chemistry of Vinylphenol-Grafted Pvdf Binder Ensuring Compatible Cathode Interphase for Lithium Batteries

Abstract Elevating operating voltage is an effective route to further promote the energy density of nickel-rich layered oxides based lithium batteries. However, high-voltage cycling generally incurs rapid capacity fade of cells due to severe decomposition of commercially available liquid electrolytes and active material degradation. Especially, reactive oxygen species including 1 O 2 generated under high-voltage cycling give rise to severe electrolyte decomposition and thus result in fast capacity fading of batteries. To address this issue, herein, we first develop a vinylphenol-grafted PVDF binder with 1 O 2 -scavenging effect for nickel-rich layered oxide cathodes, which is inspired by the eliminating role of dopamine. Detailed experiment research demonstrates that the scavenging behavior of the as-developed binder can help induce compatible cathode/electrolyte interface. Resultantly, the as-developed binder endows LiNi 0.6 Co 0.2 Mn 0.2 O 2 /Li and LiNi 0.8 Co 0.1 Mn 0.1 O 2 /Li half cells with superior cycling stability, with capacity retentions of 80.53% after 200 cycles and 87.16% after 100 cycles at 0.5 C under 3.0-4.5 V, respectively. This dopamine-inspired strategy with reactive oxygen-scavenging effect heralds an important paradigm for constructing compatible cathode/electrolyte interphase in various rechargeable lithium cells