BEIJING – The Ministry of Industry and Information Technology (MIIT) released in October a national standard on traction batteries, namely the Specification and Dimension of Traction Battery for Electric Vehicles and the Coding Standards for Automotive Traction Batteries (Draft for Comments).
The draft standard divides traction batteries into cylindrical cells, prismatic cells and pouch cells and regulates on specifications and dimensions for secondary cells, battery modules and standard battery systems.
The lack of standard on traction batteries affects all relevant parties. For battery makers, it adds to cost on production and R&D, hampers mass production, market release and technology innovation. For system integration enterprises and auto OEMs, R&D investment would be increased, technology accumulation becomes harder. Battery recycling also turns more difficult.
To certain extent, the chaotic battery market is fed by various requirements from OEMs, but many enterprises have begun to address the problem.
“We’ve unified battery standards inside our company, provided a want list of several models of cells to battery providers and select then more appropriate batteries,” said Ni Shaoyong, dean of Chery New Energy Auto Academy. Led by OEMs, followed by battery cell and pack producers to unify the standards, massive production of few models of traction batteries can be achieved to lower down purchase cost, suggested Ni.
Volkswagen will in the future simplify its EV battery unit design to cut battery cost by 66 percent. BYD has unified its battery pack standard. By mere reassembling, it can meet battery needs for different commercial vehicle models. Nanjing Golden Dragon Bus also requires its battery providers to make its batteries interchangeable.
Both auto OEMs and battery producers agree on unifying and standardizing traction batteries and the work is progressing, but not on how many kinds of cell models and dimensions should be included in the standard.
An anonymous traction battery entrepreneur says cell dimension standard should not be that specific, narrowing only to several models. The choice should be made based on the market.
Battery makers then call for another choice, to first unify size of battery box, then cells. But the call still cannot win support from OEMs.
Every OEM differs on design concepts involving things like vehicle body, lightweight to achieve differentiated competition. It is nearly impossible to have unified standard on battery box and it hampers EV product innovation, says Huang Fuliang, product director of Nanjing Golden Dragon Bus.