Electrolyte Additives - Battery Design

Electrolyte additives are used for a number of functions, including:

improved SEI formation
reduce irreversible capacity loss and gas generation
enhance thermal stability of LiPF₆
protect the cathode material from dissolution and overcharge
improve the physical properties of the electrolyte
- ionic conductivity
- viscosity
- wettability

This is a huge subject area and hence the aim of this page is to start a list of additives:

DMVC-OTMS – Incorporation of DMVC-OCF₃ and DMVC-OTMS in the VC scaffold leads to the creation of a flexible and robust SEI on the Si–C anode.

DMVC-OCF₃ – improves the creation of a flexible and robust SEI on the Si–C anode.

DTD (1,3,2-Dioxathiolane 2,2-Dioxide) – used as an electrolyte additive to reduce the initial capacity loss of the battery, reduce the battery expansion after high temperature and improve the battery charge-discharge performance and cycle times.

FEC (fluoroethylene carbonate) – used as an electrolyte additive in lithium-ion and sodium-ion batteries to improve performance and cycle life. Its decomposition forms a thin, highly flexible, and LiF-rich SEI. This LiF-rich interphase possesses high fracture toughness, allowing it to stretch and adapt to volume changes without repeatedly rupturing and consuming excess lithium — which is why FEC is used so heavily in electrolytes for silicon and silicon-graphite blend anodes, where the active material itself can swell by 200–300% on lithiation and would otherwise crack a conventional SEI apart every cycle.

LDFP (lithium difluorophosphate) – used in conjunction with PDO to improve cycle life [1].

LBOB (lithium bis(oxalate)borate) – one of the most common film-forming electrolyte additives used in lithium ion batteries.

LDFDOP (Lithium difluoro (dioxalato) phosphate) – also called as lithium difluoro(bisoxalato)phosphate (LiDFBOP) [2].

LDFOB (Lithium difluoro(oxalate)borate) – used as thermal stabilizing and solid electrolyte interface (SEI) formation additive for lithium-ion battery [5].

LTFOP (lithium tetrafluoro(oxalato)phosphate) – used to improve the life of mesocarbon microbead (MCMB)/ NCM cells for high power applications. Qin et al [4] showed that the addition of LTFOP in the electrolyte increased the initial impedance but lowered the impedance growth rate during cycling.

PDO (3-phenyl-1,4,2-dioxazol-5-one) – shown by Jeff Dahn’s group [1] to improve high temperature storage and cycle life of nickel content cells.

PS (1,3-propane sultone) – an SEI-forming additive used on both anode and cathode. Its ring-opening reaction generates lithium alkylsulfonate species that form a denser, more uniform SEI than baseline carbonate electrolytes, which lowers interfacial impedance and improves Li-ion transfer kinetics at the electrode surface rather than just protecting it [6]. Typically dosed at 0.1–1% of electrolyte mass, it is commonly paired with FEC or VC rather than used alone.

VC (vinylene carbonate) – an effective electrolyte additive to produce a stable solid electrolyte interphase (SEI) on graphite anodes, increasing the capacity retention of lithium-ion cells.