From the perspective of the recent development of lithium battery, the safety of lithium battery is improved mainly through structural innovation and the iterative upgrading of the existing material system. Thermal runaway is the main cause of battery fire and explosion. At present, Chinese lithium electric enterprises mainly improve and simplify the structure from the core, module and packaging mode, in order to reduce the risk of battery thermal runaway.

In terms of structural innovation, the risk of thermal runaway of battery can be reduced through the following three dimensions of innovation. First, intrinsic security. That is, starting from the thermal runaway mechanism of a single battery, the thermal stability of each cell material is improved at the material level, and the reliability of the cell is guaranteed through the improvement of design and manufacturing at the process level. For example, the "sandwich safety battery" developed by OPPO uses composite collector fluid instead of conventional collector fluid, which is not easy to break, to solve the safety problem of high nickel terpolymer. The second is passive safety. That is, after a single battery loses heat control, heat spread can be suppressed by heat insulation and heat dissipation measures. For example, "magazine batteries" developed by GaC Aeon and "Amber" and "Mica" batteries released by Lanto Auto are all focused on deepening insulation solutions. Third, active security. At its heart is a battery management system (BMS) that uses technologies such as big data to give early warning of thermal runaway. For example, the "100kWh battery" released by Nio integrates a thermal runaway sensor in the BMS, which can monitor the thermal pressure 24 hours a day in real time, thus improving battery safety.

In the aspect of material iteration and upgrading, a variety of technical routes develop simultaneously. In battery positive electrode material, lithium iron phosphate and three way in our country mainstream. Due to the advantages of abundant source, high safety, low cost and good cycle performance, lithium iron phosphate battery market demand is heating up in recent years, and the shipment volume has exploded. According to the China Automotive Power Battery Industry Innovation Alliance, the total number of power battery installed in China in 2022 reached 294.6GWh, up 90.7 percent year on year. Among them, the cumulative load of lithium iron phosphate battery is 183.8GWh, accounting for 62.4% of the total load, with a cumulative increase of 130.2% year on year. The cumulative loading capacity of ternary battery is 110.4GWh, accounting for 37.5% of the total loading capacity, with a cumulative year-on-year growth of 48.6%.

In terms of the installed quantity, from 2018 to 2020, the installed quantity of domestic lithium iron phosphate battery is lower than that of three-way battery. In July 2021, the market share of lithium iron phosphate batteries surpassed that of three-way batteries and has been leading ever since. In addition, with the increasing attention of lithium iron phosphate due to its safety and economy, as an upgraded version of lithium manganese iron phosphate by hot discussion again, enterprise industrialization layout also accelerated.

High specific energy battery is a global trend. How to ensure the safety while improving the energy density of power lithium battery requires an accurate grasp of the "degree". The focus is on optimizing and balancing the energy density, safety and life of the battery.