Concentrated Electrolytes Widen the Operating Temperature Range of Lithium‐Ion Batteries

Abstract

The operating temperatures of commercial lithium-ion batteries (LIBs) are generally restricted to a narrow range of −20 to 55°C because the electrolyte is composed of highly volatile and flammable organic solvents and thermally unstable salts. Herein, the use of concentrated electrolytes is proposed to widen the operating temperature to −20 to 100°C. It is demonstrated that a 4.0 mol L −1 LiN(SO 2 F) 2 /dimethyl carbonate electrolyte enables the stable charge-discharge cycling of a graphite anode and a high-capacity LiNi 0.6 Co 0.2 Mn 0.2 O 2 cathode and the corresponding full cell in a wide temperature range from −20 to 100°C owing to the highly thermal stable solvation structure of the concentrated electrolyte together with the robust and Li + -conductive passivation interphase it offered that alleviate various challenges at high temperatures. This work demonstrates the potential for the development of safe LIBs without the need for bulky and heavy thermal management systems, thus significantly increasing the overall energy density.

Research Development on Aqueous Ammonium‐Ion Batteries

“…To some extent, concentrated electrolytes, in which the activity of water is strongly suppressed, can not only virtually overcome the weakness mentioned above, but also stabilize and even improve the battery properties, which have been well proved in metallic ion batteries system. [114][115][116][117][118][119] As shown in On one hand, within a certain concentration range, the ionic conductivity of the electrolytes will greatly increase as the concentration increases, which will contribute to high power density. Du et al and Shu et al conducted studies by using 5 M (HN 4 ) 2 SO 4 and saturated (HN 4 ) 2 SO 4 as electrolytes for NH 4 -ions storage in VS 2 /VO x and Fe 4 [Fe(CN) 6 ] 3 electrodes , respectively.…”

Structural regulation chemistry of lithium ion solvation for lithium batteries

“…45,67,71,72 Moreover, when Li salt concentration of the HCE exceeds 3 mol L À1 , the corrosion of Al foil current could be suppressed to facilitate the battery to operate in a wide temperature range (À20 to ~100 C). 73,74 As demonstrated in Figure 1A,B, due to the sharp increase of Li salt, solvent molecules failed to completely occupy the solvation structure to solvate Li + , causing salt anions to be forced to enter it, producing CIP and AGGs structures. However, the high solubility and dissociation constant of Li salt is required in HCE.…”

Designing Boron‐Based Single‐Ion Gel Polymer Electrolytes for Lithium Batteries by Photopolymerization

“…Overall, membranes were thermally stable until ≈110 °C, well above LIBs operating temperature (e.g., −20 to 60 °C). [27,28] Mechanical stability through dynamic mechanical thermal analysis (DMTA) was also investigated (Figure 2b) on membranes of the same family containing different amounts of plasticizer (SIPE-GG-xx). All electrolyte membranes presented a stable storage modulus from 0 to 100 °C (in between 10 5 and 10 7 Pa), which increased with lower plasticizer content, having its maximum with the SIPE-GG solvent-free membrane (≈5 × 10 6 Pa).…”