Aerogel materials can not only solve the safety problems of the current ternary battery system and other battery systems, but also play a flame retardant role in automotive interior materials.
1. The application of power batteries is imminent, and it is expected to solve the safety pain point
The high temperature tolerance of aerogel solves the safety pain point of ternary batteries. When the on-board battery outputs electricity for a long time, the chemical reaction in the battery for a long time will cause the battery body to heat up significantly, and there is a risk of combustion and explosion. Traditional core modules use plastic partitions to separate the batteries from each other, which is not practical. This is not only heavy but also unable to play a protective role, and it is easy to cause the battery temperature to be too high, resulting in the dissolution of the partition and fire. The existing protective felt used has a simple structure and is easy to deform, so that it cannot be well in contact with the battery pack. When the battery heats up severely, it cannot play a good heat insulation effect. The emergence of aerogel composite materials is expected to solve this pain point.
Ternary batteries have higher safety requirements. Its advantages lie in energy storage density and resistance to low temperatures: 1) Energy storage density. The energy density of ternary lithium batteries is 170-200Wh/kg, and the energy density will be further improved in the later stage, while the energy density of lithium iron phosphate batteries is 140-160Wh/kg; 2) Low temperature performance. The lower limit of low temperature use of ternary lithium batteries is -30℃, and the lower limit of low temperature use of lithium iron phosphate batteries is -20℃. Under the same low temperature conditions, the attenuation of ternary lithium batteries in winter is less than 15%, and the attenuation of lithium iron phosphate batteries is as high as more than 30%. However, due to the higher energy density of ternary batteries, the stability and safety of the batteries are relatively poor. When in use, they rely more on high-performance flame retardant materials to enhance the safety performance of the ternary battery system.
Power batteries are developing rapidly, and ternary batteries account for the majority of the share. Data show that from January to July 2020, the cumulative installed capacity of power batteries in my country reached 22.5GWh. Among them, the cumulative installed capacity of ternary batteries is 15.9GWh, accounting for 70.6% of the total installed capacity; the cumulative installed capacity of lithium iron phosphate batteries is 6.5GWh, accounting for 28.8% of the total installed capacity. It is estimated that the global shipments of ternary positive electrodes will reach 1.5 million tons in 2025.

Aerogel composites, as flame retardant materials, have advantages over traditional flame retardant materials such as light weight, excellent flame retardant performance, and good environmental performance. At present, there are two main types of thermal insulation and flame retardant materials used in new energy vehicle battery core modules: 1) Plastics such as PP, ABS, PVC, etc., among which ABS engineering plastics are the main ones. Flame retardants are usually added to PP, ABS and other plastics to make flame retardant plastics; 2) Fireproof felts made of fireproof materials such as glass fiber and ceramic fiber wool. As an emerging material, aerogel has excellent thermal insulation and flame retardant properties. Aerogel composites made by compounding aerogel with engineering materials have extremely excellent flame retardant properties. The SiO2 aerogel glass fiber felt composite material developed by Pan Asia Microporous has a thermal conductivity of less than 0.017W/(m〃k) at room temperature of 25℃ and a thermal conductivity of between 0.047~0.066W/(m〃k) at a high temperature of 600℃. It can increase the high temperature tolerance of the battery pack to above 800℃.

This type of aerogel composite material can withstand the instantaneous impact of high-temperature energy caused by a short circuit in the battery pack, and better solve the safety problem of power batteries. According to the requirements of the "Safety Technical Conditions for Electric Buses", the rechargeable energy storage system (or installation cabin) and the passenger cabin should be isolated by flame-retardant insulation materials. The combustion performance of the material should meet the Class A non-combustible requirements specified in GB8624-2012, and the thermal conductivity should be less than or equal to 0.04W/(m〃k) at 300℃. Patent CN210136903U discloses a silica aerogel felt product for new energy vehicle batteries. Each surface of the silica aerogel felt layer is covered and connected by a high-silica glass fiber cloth layer, and the covering opening is connected by a high-silica wire. The material meets the UL94 V0 non-flammable performance index required for new energy vehicles. The thermal conductivity at 400°C is less than or equal to 0.04W/(mk). It can work for a long time at a high temperature of 800°C. It meets the conditions of lithium-ion power battery cells being isolated and withstanding the high-temperature energy released instantly by the faulty battery cells when a short circuit or overcharge occurs and the fire of the battery cells does not expand or extend.

It is estimated that the potential scale of aerogel composite materials in the domestic new energy vehicle market will be about US$628 million in 2025. According to Aspen Aerogel's 19th annual report, the average price of aerogel materials in recent years is about US$30/square meter. Each new energy vehicle requires about 2-5 square meters of aerogel composite materials, and each new energy vehicle requires an average of US$105 worth of aerogel composite materials. According to the requirements of the "New Energy Vehicle Industry Development Plan (2021-2035)", by 2025, the sales volume of new energy vehicles will reach about 20% of the total sales volume of new vehicles. Xin Guobin, Vice Minister of the Ministry of Industry and Information Technology, said that according to the plan, the annual compound growth rate must reach more than 30%.
It is estimated that the potential scale of aerogel composite materials in the global new energy vehicle market will be about US$1.575 billion in 2025 and US$3.150 billion in 2030. New energy vehicles are also the mainstream development direction in the world. According to the planning goals of mainstream car companies, the corresponding global sales will be close to 15 million vehicles in 2025 and will reach 30 million vehicles in 2030.
2. There is also room for optimization in traditional automotive applications
Aerogel flame-retardant composites not only have better flame retardant and hydrophobic properties, but also can enhance the strength of the material matrix to improve its toughness. After specific modification, silica aerogel can have a larger specific surface area, and it has a strong interface adhesion with high molecular polymer matrices such as plastics and rubber, which improves the dispersion and fluidity of composite aerogel flame retardants in polymer melts and improves the flame retardant effect. Among them, the thermal stability and thermal decomposition temperature of the modified rubber are improved to varying degrees.
Aerogel materials can be added with flame retardants to be used in conjunction to prepare flame retardant materials with better performance, and the potential market space is also large. Aerogel flame retardant materials can also be widely used in different scenarios, such as different parts of the car, such as seat flame retardant lining and body flame retardant lining, which can replace traditional thermal insulation flame retardant materials. Its flame retardancy can curb the spread of fire, and its low smoke density characteristics will reduce the lethality of fire, greatly reduce fire hazards, and protect the safety of passengers.