In the world of technology, nothing is passe. What goes out eventually comes back in some other form. It is a fascinating rites of passage. Take for instance, batteries in cylinder shape. Some years back they gave way to ones in rectangular form. They were otherwise referred to as prismatic and pouch batteries. Notebooks and handsets were particularly quick to adapt them.
But in the EV industry Tesla, which is a kind of disruptor, decided to stay away from the beaten path. The Elon Musk-helmed company went it for battery pack that was cylindrical in shape.
Its battery cell, now known as 4680, is bigger, offers six times the power of Tesla’s previous cells, and five times the energy capacity. The 4680 battery gets its name after the fact its dimensions are: 46mm (diameter) by 80mm (height.
But why cylinder batteries?
Tesla created the the first tabless cylindrical cell design to address the thermal issues. The company also said that the cylinder form factor of the cell results in a five-times increase in energy, six-times increase in power capacity, and 16% increase in range. It also results in a 14% reduction in cost per kWh — again, at the cell form factor level only.
Considering all these, other EV-makers are evincing interest in cylindrical batteries. According to the Korean site The Elec, battery maker Samsung SDI, who is angling to be supplier of 4680 battery to Tesla, is now working on shorter cells with the same diameter for other car manufacturers.
"BMW, General Motors and Stellantis are some of the companies planning to adopt cylinder batteries on their EVs," the report claimed.
Tesla's existing battery suppliers, for the record, include Panasonic, LGES and CATL. Samsung SDI is said to be trialing batteries with the diameter of 46 mm and a height of between 40 and 60 mm. The shorter variants provide options to in the design of modules and packs but also to reduce production problems. Two battery cells each with a diameter of 46 mm and a length of 40 mm (4640 cell) could be stacked on top of each other, creating a battery pack with two layers.
BMW has already announced that it was developing a new generation of batteries for its 'New Class' electric cars. "We want to significantly increase the energy density of the cells and reduce the costs of material use and production at the same time. We will also significantly reduce the use of primary material to ensure a truly ‘green’ battery," BMW said and hinted that it is evaluating different cell formats, cell chemistries and also cell modules. BMW’s new round cells are said to exceed the energy density of Tesla’s cells.
As cylindrical battery cell format brings a host of performance, manufacturing, and cost benefits to the table, its comeback now looks certain.
