In order to solve the problem of high battery costs and improve profit margins, many Chinese car companies have begun to directly enter the battery supply chain in various ways. Automakers such as Geely and NIO, for example, have set up their own battery subsidiaries in the hope of reducing costs. This article has been compiled to introduce the independent battery operations of BYD, SAIC and GAC Motor, as revealed at the 7th International Summit on Power Battery Application held in Shanghai.
BYD’s Blade Battery
Since the beginning of this year, BYD has become one of the fastest growing battery firms in the world. In terms of monthly rankings for the second half of the year, the Shenzhen-based firm surpassed South Korea’s LG Energy Solution to place second globally. BYD’s blade battery contributed greatly to this positive business trajectory.
In March 2020, BYD released its “blade battery.” This name refers to the slender and flat shaped lithium-ion battery battery cells resembling blades (their typical size is 13.5mm x 90mm x 960mm). The interior adopts a stacked design, and the cells are directly integrated into the bottom of the battery pack, thus eliminating the module structure.
According to Shenzhen-based FinDreams Battery, the battery business subsidiary of BYD, the firm has built a blade battery cell platform. Blade battery cells can be divided into “long blades” (length greater than 700 mm), “short blades” (length 400-700 mm), and “square blades” (height greater than 150 mm), according to their shapes. Battery packs grouped with different types of blade batteries can meet the space and voltage requirements of different vehicle models.
However, although this type of battery has passed various safety experiments, cars equipped with them frequently become hot topics due to their spontaneous combustion. According to domestic media statistics, there were 18 spontaneous combustion cases (including “suspected” cases) involving BYD vehicles in the first half of 2022, including one Dolphin model, two Qin PLUS DM-i models, one Qin Pro EV, one Song Pro EV, three Tangs and nine Tang DM-i models. All the spontaneous combustion models were equipped with blade batteries, and most of them were super hybrid models (DM-i).
SAIC’s Mofang (Rubik’s Cube) Battery
In August of this year, Shanghai-based Chinese state-owned automaker SAIC released its “Mofang Battery,” which focuses on ultra-high integration, ultra-long life and “zero thermal runaway” safety protection, also supporting the separation of vehicles and batteries. This product is a standard battery pack with a fixed length and width of 1300mm x 1690mm. There are three height options, including 110mm, 125mm and 137mm.
The battery pack adopts LBS cell and CTP technology (Cell To Pack Modular-Free Technology). The thickness of a single battery pack is as low as 110mm, and the battery mass grouping efficiency can reach 75%-80% and the volume grouping efficiency can reach 59%-62.3%. This greatly improves vehicle efficiency.
The battery system can cover cruising ranges of 400km to 800km, depending on the precise model. SAIC is developing a “golden standard battery” with a length battery life of over 1,000km and a super-fast charging “black standard battery” based on an 800V voltage platform, which can be charged for 5 minutes for a range of 200km. This super-fast rechargeable battery project has entered the sample stage and is scheduled to begin mass production in June next year.
The battery is also the result of in-depth cooperation between SAIC and CATL, one of the world’s leading battery giants. CATL stated that it has authorized relevant CTP technology to SAIC, and that both sides have cooperated to complete production.
GAC’s High Specific Energy Silicon Negative Electrode Cell
Aion, a Chinese electric vehicle marque under Guangzhou Automobile Corporation (GAC), has been developing its own batteries for a long time now. In the same year when GAC Aion was established in 2017, the company realized the mass production and installment of battery packs independently designed for its first BEV model, and it also started the independent development of batteries. In 2021, it released technologies such as the magazine battery, sponge silicon negative battery and super-speed battery.
Among them, the “high specific energy silicon negative electrode cell” is the earliest independent system of GAC Aion. This product is equipped with a square aluminum shell with an energy density of 280Wh/kg. It adopts a high nickel positive electrode and silicon negative electrode material system, while silicon-based negative electrode material has more advantages than traditional graphite negative electrode in gram capacity, and high and low temperature performance. The Aion LX Plus model is equipped with this battery cell, making it GAC Ean’s first pure electric mass production model with a cruising range of over 1,000km.
In addition to conventional lithium iron battery products, the company has also introduced a new-generation super iron lithium battery built on microcrystalline technology (SmLFP), which aims to improve the inherent defects of lithium iron phosphate materials in low temperatures, while ensuring better cycle performance. The new battery can be recycled more than 4,000 times, maintaining an 80% capacity retention rate, corresponding to the overall cruising range of the whole vehicle exceeding 1.5 million km.
Different from BYD and SAIC, GAC Aion’s top priority is to accelerate the implementation of the first batch of self-produced batteries. The main suppliers of the company’s electric vehicle batteries are CALB, CATL and Farasis Energy.