Liu Shen has secured a final victory in a patent invalidation case concerning high rate charge discharge of lithium iron phosphate (LFP) batteries. The Supreme People's Court granted the patentee's application to withdraw its appeal, rendering the decision of the China National Intellectual Property Administration (CNIPA) that the entire patent be invalidated legally effective.

Centering on LFP cathode material and electrode sheet structure technologies, this case had three major domestic power battery enterprises as joint petitioners for invalidation, of which our firm represented one petitioner to institute the invalidation proceeding. CNIPA finally invalidated all claims of the subject patent on the ground that the claims were not supported by the specification. This invalidation decision delivers industry leading interpretations on multiple legal issues applicable to patents defined by formula based parameters, including experimental design and sufficiency of support for endpoint values. Notably, during the administrative proceeding, the patentee proposed a settlement with our client and requested our side to withdraw the invalidation petition. Nevertheless, CNIPA held that based on the completed examination work, a decision invalidating the subject patent could be rendered. Further, since invalidation grounds had also been raised by the second petitioner, the examination proceedings would not be terminated. This circumstance attests to the robustness of our invalidation grounds and evidence corpus.

The case was handled by ZHANG Xiang and WANG Xiao.