Square batteries made their entry into the automotive industry alongside cylindrical batteries. Japan’s sanyo electric was among the first to develop square batteries, introducing the square lithium-ion secondary battery in 1995. These batteries, made of aluminum alloy, were about 30% lighter than their steel counterparts, making them increasingly popular in products like mobile phones.
In 2008, panasonic acquired sanyo electric, gaining access to the square cell technology. However, it’s important to note that panasonic did not export this technology to tesla. Square battery production was considered more challenging than cylindrical batteries, according to a battery industry expert, although they were relatively easier to assemble. Despite the difficulty, square batteries showed potential for becoming an important direction in the automotive industry.
From vda to module 590:
while square batteries made their debut in the automotive sector around the same time as cylindrical batteries, they initially faced limited progress due to insufficient support from popular models. However, by 2012, panasonic’s square batteries found adoption in vehicles from prominent companies like volkswagen, toyota, and ford. Models such as volkswagen e-golf, e-up, golf gte hybrid, audi q5 and a6 hybrids, toyota eq, prius phv1, ford fusion2, and others started using panasonic’s square battery technology.
Among the earliest square cells from panasonic, the 5ah cell was designed to fit the dimensions specified by vda hev, which measure 1208512.5. Toyota’s clarity phev also employed panasonic’s square batteries, matching the size of vda phev2, and were much larger for plug-in models.
Samsung sdi later mastered square cell technology, with battery sizes suitable for models like bmw i3, conforming to bev2 in vda size, which measures 17345125. The growth of samsung’s square power battery followed a similar trajectory as japan’s panasonic, gaining popularity in markets outside china. Square battery sizes also expanded, mainly focusing on continuous extensions in thickness and length.
The trend of overall electrification in europe involves gradual battery enlargement, following the development path of 48v, hev, phev, and then bev.
Square batteries have become the most popular vehicle battery shape in china. Initially, chinese companies adopted the european vda standard size around 2012. However, the limited maximum capacity of 120ah under this size could no longer meet the demands of chinese car companies by 2017-2018. As a result, samsung sdi and other chinese companies started breaking away from the vda size standard. In 2017, volkswagen considered launching the pure electric meb platform, introducing the 590 module to accommodate larger battery cells.
Increasing the size of square batteries has become a global direction pursued by car manufacturers worldwide.