Specific Electrolyte for High-Performance Lithium-Ion Battery {LiFePO4 + Graphite}, 200 g/bottle, CHPLIBSELFPG

Operating a lithium-ion cell with a Lithium Iron Phosphate ({LiFePO4 / LFP) positive electrode paired with a Graphite (Gr) negative electrode presents a distinct electrochemical environment compared to high-voltage cobalt or nickel chemistries. LFP operates at a flat, moderate potential plateau (~ 3.4 V vs. Li/Li+) and possesses an exceptionally stable olivine crystal structure that does not suffer from lattice oxygen release or severe transition metal dissolution. Consequently, the primary electrolyte engineering goals for LFP // Graphite cells shift away from high-voltage oxidative shielding toward low interfacial resistance, wide temperature operational stability, minimal iron dissolution, and long calendar/cycle life.

The recommended electrolyte recipe are shown below: (1) Salt Framework: 1.0 M to 1.2 M Lithium hexafluorophosphate (LiPF6). LiPF6 provides an optimal balance of ionic conductivity, thermal dissociation, and critical passivation of aluminum current collectors at moderate potentials (~3.5 V). Dual-salt variations (adding 0.2–0.5 M LiFSI) are sometimes utilized for ultra-low temperature or high-rate capability, but standard LiPF6 remains the commercial baseline for cost-effective longevity. (2) Solvent Architecture: Ethylene Carbonate (EC) blended with linear carbonates such as Ethyl Methyl Carbonate (EMC) or Dimethyl Carbonate (DMC). A standard baseline ratio is EC:EMC = 3:7 or 3:8 (by weight). (3) Essential Functional Interphase Additives: (i) 1.0 wt% to 2.0 wt% Vinylene Carbonate (VC): The gold-standard passivating additive for LFP // Graphite systems. VC undergoes preferential two-electron reduction on the graphite anode during initial formation, building a stable, low-impedance polymeric/inorganic SEI that suppresses continuous electrolyte consumption and prevents gas generation. (ii) 0.5 wt% to 1.0 wt% Fluoroethylene Carbonate (FEC): Often co-added in minor amounts (especially for wide-temperature formulations) to further enhance low-temperature charge acceptance and stabilize the graphite interphase. (iii) 0.5 wt% Lithium difluoro(oxalato)borate (LiDFOB) or LiBOB (Optional): Assists in mitigating trace iron dissolution from the LFP cathode over extended high-temperature storage (calendar aging).

Notes: Please store the specific LIB electrolyte in the glovebox due to its sensitivity to humidity.

References: 

1. Z. Li, et al. Electrolyte Design Enables Rechargeable LiFePO4/Graphite Batteries from −80 °C to 80 °C, Angew Chem Int Ed, 2025, 64, e202409409
2. D. Guan, et al. Reconstructing Solvation Structure via Strongly Nucleophilic Anions for High-Rate and Low-Temperature Graphite||LFP Pouch Cells in PC-Based Electrolyte, Adv. Energy Mater., 2026, 16, e71406