China's EV Makers Say They Build Their Own Batteries. Do They?
When a Chinese carmaker announces it has developed its own battery, the first question from outsiders is usually the wrong one: does it run its own cell factory? Most do not. Li Auto, Xiaomi, Leapmotor and Xpeng have all pushed the phrase “self-developed battery” into their marketing this year, and skeptics inside the industry have been quick to call it a slogan rather than a technology.
The carmakers answer that making the cell is not the point. A modern electric vehicle’s battery is not a single product but a stack: the cell itself, the module and pack design, the thermal management that keeps it alive in a northern winter, the software that decides how fast it charges and how much energy it releases, and the supply contracts that set the price. A company can buy cells from a supplier and still own most of that stack — and most of the cost.
That is where the tug of war sits. Battery makers such as CATL built their position by selling complete packages to carmakers, and for years the relationship looked like a straightforward supplier deal. As electric vehicle volumes grew, the balance shifted: the battery is the single most expensive part of the car, and whoever controls its specification controls a large share of the vehicle’s price, weight, range and safety story.
Doing the pack and the software in-house gives a carmaker room to tune the car around the battery rather than the other way round. It also gives it a second supply option, which matters in a market where cell prices have swung hard and where a single supplier’s allocation can decide whether a model ships on time. Several of the companies now claiming self-developed batteries have signed joint development deals with cell makers rather than building fabs of their own.
The economics explain the enthusiasm. If a carmaker designs the pack, it can squeeze more range from the same cells, cut weight, and keep a slice of the value that would otherwise go to the supplier. It can also advertise a number — charging speed, range, a safety test result — that customers can compare on a showroom floor. The battery becomes part of the brand rather than a component buried in a spec sheet.
For the battery giants, the risk is not losing the cell business but losing the interface with the customer. If carmakers own the pack design and the battery management software, the supplier becomes a manufacturer of commodity cells, competing on cost and yield. That is a very different business from the one that made CATL one of the most valuable industrial companies in China.
The next phase will be decided by who can actually deliver. A self-developed battery that ships in volume, holds its range after several winters and passes safety tests without recalls is a real capability. One that exists mainly in a launch presentation is not. Chinese buyers have become unusually well informed about battery specifications, and they compare packs the way buyers elsewhere compare engines.
Watch the supply agreements rather than the press releases. When a carmaker that claims a self-developed battery signs a long-term cell contract with an outside supplier, that tells you where the real boundary sits: the carmaker owns the design and the software, the specialist still owns the chemistry. That division of labour may turn out to be the durable model for the industry — and the one that decides which Chinese brands keep their margins as prices keep falling.