{'fraction_non_alphanumeric': 0.032974001268230815, 'fraction_numerical': 0.013316423589093214, 'mean_word_length': 5.188235294117647, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Low-Cost Li||SPAN Batteries Enabled by Sustained Additive Release

Batteries with energy densities exceeding that of current lithium-ion cells with reduced materials cost are vital to the future of electric transportation. Although Li||sulfurized polyacrylonitrile (SPAN) batteries have the potential to meet both of these goals, the integration of low-cost electrolytes that are simultaneously stable with both Li and SPAN limits their application. Herein, we present a scalable approach to remedy this issue. This approach utilizes LiNO3 as a solid additive to the cathode, which is specifically enabled by an electrolyte based on diethyl ether (DEE), having sparing solubility to LiNO3 and a Li metal cycling efficiency of 99.0%. The sustained release of LiNO3 into the electrolyte was found to produce a cathode electrolyte interphase (CEI) composed of S−O and F species that is correlated with a SPAN cycling retention of 85% after 200 cycles. This interphase was characterized via X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FT-IR), and scanning transmission electron spectroscopy (STEM). This endowed stability on the cathode side, in addition to the high Li metal reversibility, allowed for the assembly of a 40 μm Li||3.5 mAh cm−2 SPAN (2 wt % LiNO3) full-cell that exhibited stable cycling over 100 cycles. This study provides a viable method for the construction of Li||SPAN batteries with a nonfluorinated electrolyte at a dilute salt concentration, allowing for the low intrinsic cost of SPAN to carry over to the system level.