Context: Contemporary Amperex Technology Co., Limited first sued its local rival China Aviation Lithium Battery in July 2021, enforcing five patents and seeking over 188 million Chinese yuan (US$25 million) in damages. CATL has scored some victories, so far securing over 44.53 million Chinese yuan (US$6 million) in compensation – before enforcing a sixth patent against CALB in the Fuzhou Intermediate Court last July. CATL has had setbacks too, however, with the Supreme People’s Court in December 2023 dismissing suits it had brought for its “cathode sheet and battery” and “lithium-ion battery” patents. October saw CALB bring its first counterclaim against CATL for 1 billion Chinese yuan (US$136 million), in which it alleged that the EV battery giant and Tesla Automotive Sales and Service (Wuhan) Co., Ltd. infringed four of its own battery patents. However, a month later, the China National Intellectual Property Administration (CNIPA) invalidated two of those patents.
What’s new: CATL has sued CALB again, this time in the Hangzhou Intermediate Court, for infringing on a patent related to secondary battery technologies. In the same suit, it also alleges that Hangzhou Pengxing Automobile Sales Service Co., Ltd. has infringed its top cover component patent. It is claiming a total of 90 million Chinese yuan (US$1.23 million) in damages.
Direct impact: This is the seventh patent CATL has enforced against CALB, with a cumulative claim of over RMB 700 million (US$95.6 million) in damages. This particular action may be in response to CALB’s October claim (January 3, 2025 HK Stock Exchange announcement), meaning the CNIPA’s decision in November did not help CALB reconsider its litigation strategy and the battery makers’ saga is far from over.
Wider ramifications: CATL’s ongoing battle against CALB is only one of several patent disputes between electric vehicle battery makers in China, which seem to be adopting increasingly offensive IP strategies. Intense market competition in the world’s largest exporter of EV batteries, as well as an increasingly patentee-friendly litigation venue, are just two of several reasons lawyers ip fray spoke with have mentioned.
As of November 2024, CATL owned 37% of the global market share for EV batteries, and was closely tailed by fellow Chinese players BYD and CALB, and South Korea’s LG New Energy. CATL owns over 20,000 active granted patents and has enforced them by filing claims spanning from unfair competition to trade secret misappropriation.
In this most recent action, the patent-in-suit is:
- China patent no. 202210514746 (“Top cap subassembly and secondary cell of secondary cell”)
Liu Shen & Associates partner Michael Zhang, who has previously worked on CATL’s years-long case with CALB, notes that a major reason why the EV battery field is seeing so many disputes is because of intense market competition. “With the rapid development of China’s EV market, batteries – as core components – have become increasingly competitive,” he says. Companies are using legal means more and more to protect their interests and maintain their market share and technological advantages, making litigation an important form of competition, he adds.
Zhang also points to the increasing amounts of damages being awarded in Chinese patent disputes, which might motivate companies to enforce their rights more actively – and the way in which IP enforcement has been used as a tactic to “severely impact the IPO process”. In 2019, 33 IPO applications were terminated without a listing taking place, and in 17 of those instances, IP-related deficiencies were among the issues cited by regulators’ objection letters. Later, between 2019 and 2021, patent infringement lawsuits accounted for 3.5% (274 cases) of the total 7,839 judicial lawsuits filed by STAR Market-listed companies.
There is also a notable disparity in strength among EV battery players. Zhang says:
“CATL is significantly ahead of other EV battery companies in terms of market share and intellectual property holdings. This disparity also makes CATL more proactive in protecting its rights, leading to more disputes.”
He notes that BYD is not included in this bracket as it uses its self-manufactured EV batteries for its electric vehicles, thus has fewer disputes with external parties.
Sum Lam, Eversheds Sutherlands Head of Patents, Asia, agrees that an expanding market has led to the increased number of disputes: as the amount of damages obtainable is higher – evidenced by those awarded in CATL’s dispute with CALB – and the incentives to obtain injunction to stop the infringement of patent to protect its own sales is also higher.
Lam also points to the increased cooperation between Chinese battery manufacturers and multinational corporations involved in the EV supply chains – including when Belgium’s Umicore sued several Chinese battery manufacturers (such as Ningbo Ronbay New Energy) but had those patents-in-suit invalidated.
But there are several more reasons for the intensified litigation we are witnessing, he says, including:
- a shift in the mindset of domestic battery manufacturers;
- inherent difficulties in ascertaining which companies the patents are attributable to if employees were poached, as observed by the Supreme People’s Court (March 26, 2024 article);
- problematic patent applications; and
- patent war as a business strategy.
China’s EV battery litigation space
CATL’s four-year war against CALB joins several other high-profile EV battery disputes in China, including the following:
- CATL v. Tafel New Energy Technology: Prior to targeting CALB, CATL’s first-ever patent infringement dispute was launched against Tafel in 2020, over the infringement of patents for safety-related battery technology. It sought 120 million Chinese yuan (US$17 million) in damages. In 2021, the Higher People’s Court of Fujian sided with CATL, ordering Tafel to halt the manufacture and sale of several infringing battery models and pay 23 million Chinese yuan (US$3 million) in damages. The case is still pending.
- Ningde Amperex Technology Limited (ATL) v. Zhuhai Cosmx: An ongoing case filed in the Fuzhou Court – worth noting it involves 3C batteries, not EV power batteries, and that it was also filed in the Eastern District of Texas. In its case in the U.S., ATL secured a rare, enhanced damages award in April last year – which counsel for the plaintiff Quinn Emanuel Urquhart & Sullivan claimed marked the first-ever enhanced damages awarded to a Chinese plaintiff in this popular patent venue.
- Celgard v. Shenzhen Senior Technology Material: This case was initiated by Celgard in the U.S. in 2019, and involved the alleged infringement of patents related to ceramic-coated and polypropylene separators. Celgard sued Shenzhen Senior Technology Material Co. Ltd. for patent infringement and trade secret misappropriation. Senior later filed an antitrust complaint against Celgard in the Shenzhen Intermediate People’s Court. A year after its initial action, Celgard sought and secured an injunction against Senior in the UK. But the companies then reached a settlement in November 2023, and all the cases were dismissed.
- Umicore v. Ningbo Ronbay Lithium Battery Material: Belgium’s Umicore enforced patents related to cathodes used in vehicle batteries against Ronbay in the Ningbo Court in 2020 and 2021, seeking 312 million Chinese yuan (US$42 million) in damages, collectively. The first complaint was dismissed, however, while Umicore withdrew the second.
- Umicore v. Jiangsu Easpring Material: In a separate case, Umicore also sued Easpring in the Suzhou Intermediate People’s Court.
- Shanghai Energy New Materials Technology (SEMCORP) v. Gellec: SEMCORP sued its rival lithium-ion battery separator manufacturer Gellec in four separate actions between May and August 2023, claiming it had infringed several patents related to its lithium-ion isolation film. The plaintiff was seeking combined damages of 280 million Chinese yuan (US$38 million) but withdrew all but two of its suits following patent invalidation decisions by the China National Intellectual Property Administration. The remaining two are still pending.
- Enjie v. Jinli: Enjie had sued its battery separator manufacturer rival Jinli over two patents, claiming 50 million Chinese yuan (US$6.8 million) and 99 million Chinese yuan (US$13.5 million) for the alleged infringement, respectively. However, the CNIPA invalidated both patents in separate decisions in October and November. Enjie has since withdrawn its lawsuits.
Some major Chinese EV battery manufacturer litigations have also spilt over into, or directly been filed, in the U.S. They include Maxell v. ATL, Advanced Electrolyte Technologies v. BYD, Varta v. EVE Energy, and MU Ionic Solutions v. CATL.