Nonflammable All-Fluorinated Electrolyte Enabling High-Voltage and High-Safety Lithium-Ion Cells.

In this study, a nonflammable all-fluorinated electrolyte for lithium-ion cells with a Li(NiMnCo)O cathode is investigated under high voltages. This electrolyte, named FT46, consists of fluoroethylene carbonate (FEC) and bis(2,2,2-trifluoroethyl) carbonate (TFEC) in a mass ratio of 4:6. Compared to a commercially available electrolyte and several other fluorinated electrolytes, cells containing FT46 demonstrate significantly better cycling performances under high voltage (3.

Application of Polyethylene Glycol-Based Flame-Retardant Phase Change Materials in the Thermal Management of Lithium-Ion Batteries.

Composite phase change materials commonly exhibit drawbacks, such as low thermal conductivity, flammability, and potential leakage. This study focuses on the development of a novel flame-retardant phase change material (RPCM). The material's characteristics and its application in the thermal management of lithium-ion batteries are investigated.

Thermal runaway features of large-format power lithium-ion cells under various thermal abuse patterns and capacities.

Herein, a comprehensive investigation is performed to research the thermal runaway features of large-format power lithium-ion cells under various heating patterns (2 kW electric heating oven and 600 W electric heating plate) and capacities (60, 150, and 180 Ah). Although the electric heating plate induces the cell to encounter thermal runaway earlier in comparison with the electric heating oven, the combustion does not appear for the former case since the compact stacking of the electric heating plate restrains the heat release of the heater such that the surrounding temperature is too low to induce the ignition of the thermal runaway combustibles. Besides that, it is interesting to find that the color of the ejected products under the electric heating plate condition becomes shallower as the thermal runaway proceeds, which implies that the ejecta in the initial of thermal runaway is mixed with quantities of solid particles and the proportion would gradually decrease.

Impact of safety valves on thermal runaway characteristics of 21 700-size lithium-ion cells.

To demonstrate the impact of safety valves on the thermal runaway characteristics of 21 700-size lithium-ion cells, this work carries out a series of abusive tests including over-heating tests, accelerating rate calorimetry (ARC) tests and overcharge tests; in the meantime, the impact of safety valves on cells with various states of charge (SOC) and states of health (SOH) is unveiled accordingly. Safety valves have a great impact on the thermal runaway behavior of 21 700-size cells, which effectively restrains the thermal runaway risks and hazards of cells under the over-heating conditions. The presence of a safety valve could even prevent a cell from the thermal runaway induced by overcharge.

Data and video for the thermal and fire propagation of multiple lithium-ion batteries.

The data presented in this article are related to research article "Investigation on thermal and fire propagation behaviors of multiple lithium-ion batteries within the package" (Chen et al., 2019). This data article provides the data information including the experiment pictures, flame temperatures, pressure and heat flux sensors temperatures, and gas concentrations of 6 × 6 batteries and 10 × 10 batteries.

Influence of low temperature conditions on lithium-ion batteries and the application of an insulation material.

In the current work, a series of experiments were carried out under low and normal temperature conditions (0 and 20 °C) to research the influence of low temperature on the performance of lithium-ion batteries (LIBs). Besides this, a commercial insulation material (IM) was employed to research its effect on preventing damage in a battery exposed to low temperature. Based on the experimental results, it was found that the battery exhibited a higher temperature increase at low ambient temperature due to the larger internal resistance of the battery at low temperature, which resulted in greater heat generation.

Investigation of a commercial lithium-ion battery under overcharge/over-discharge failure conditions.

A lithium-ion battery (LIB) may experience overcharge or over-discharge when it is used in a battery pack because of capacity variation of different batteries in the pack and the difficulty of maintaining identical state of charge (SOC) of every single battery. A series of experiments were established to investigate the thermal and fire characteristics of a commercial LIB under overcharge/over-discharge failure conditions. According to the results, it is clear that the batteries experienced a clear temperature rise in the overcharge/over-discharge process.