An ongoing dispute over the performance of BYD’s second-generation Blade Battery has intensified after automotive blogger Cai Shen Dao announced that the company filed a police report against him. Cai shared in a July 30 post on Weibo that he delivered hundreds of pages of test records and related materials to investigators at the Songjiang District Police Station in Shanghai. Neither BYD nor the Shanghai Songjiang police have publicly confirmed the report or disclosed whether a formal investigation is underway.
Earlier this month, Chinese regulators suspended Cai’s social media activities under the Shenzhen Cyberspace Administration’s Qinglang campaign. Official summaries carried by state media cited the dissemination of misleading product testing information and harm to corporate reputation. The restrictions reportedly block Cai from posting, commenting, or monetizing his account.
The dispute originated in May, when Cai livestreamed a fast-charging test of a Fangchengbao Tai 3 equipped with BYD’s Blade Battery. He charged the vehicle from 8% to 97% state of charge while monitoring five external temperature probes. These probes registered a peak surface temperature of 76.42 °C, compared to approximately 71.0 °C shown by the vehicle’s battery management system (BMS). Probe placement produced a maximum surface temperature variance of about 6.5 °C. Critics have questioned whether externally measured cell-surface readings can be directly compared to internal BMS data from a sealed production pack.
Later in May, Cai’s team performed a destructive teardown on a frozen Blade Battery pack. The eight-hour process revealed a 170-cell series configuration, a grid-like reinforcement structure, direct refrigerant cooling channels, a pack weight near 572 kg, and a calculated integration efficiency of roughly 73.6%. Dismantling compromised the pack’s adhesives, cooling interfaces, and insulation, altering its factory-sealed state.
Following the social media restrictions, Cai engaged the Guolian Research Institute—part of the China National Power Battery Innovation Centre—to repeat the fast-charge test under laboratory conditions. Charging from 7% to 97% in 8 minutes 32 seconds, the lab recorded a peak 1,200 A charging current, an external cell-surface peak temperature of 78.5 °C, and a BMS reading of about 70.5 °C, yielding an 8 °C difference. Measurements were taken on exposed cell surfaces rather than through original pack assemblies.
On July 31, Cai published screenshots of an alleged May 5 communication from an agency he said represented BYD regarding potential commercial cooperation. The authenticity of those messages and the agency’s link to BYD remain unverified. Cai also cited China’s draft Anti-Network Violence Law, though no authority has indicated it applies to this case. To date, there is no public court judgment, police conclusion, or official investigative outcome related to the reported filing.
Source: Car News China (https://carnewschina.com/2026/07/31/byd-blade-battery-2-0-dispute-escalates-after-blogger-says-automaker-filed-police-report/)
