Gasgoo Munich-EVE Energy held a product launch and production-line ceremony at its Chengdu base on October 20, according to a post on BYD's WeChat account, unveiling its Longquan No. 3 2.0 all-solid-state battery and a sodium-ion battery solution for electric two-wheelers. Three products—the Longquan No. 3 2.0, a polyoxygen all-solid-state battery and a solid-liquid battery—also rolled off the production line.
Image source: EVE Energy
All-solid-state battery targets brain-computer interfaces
The Longquan No. 3 2.0 all-solid-state battery is designed for brain-computer interface (BCI) applications. The technology has the potential to help patients with paralysis or speech impairments regain certain functions through brain-controlled interactions.
Non-invasive BCI systems face challenges including limited signal precision, restricted functionality and reliance on external headsets, making large-scale deployment difficult. Invasive systems can deliver stronger signals with less noise, enabling deeper human-machine interaction and the restoration of visual and auditory functions. However, batteries implanted in the skull must meet stringent requirements for biocompatibility, long-term sealing, leak prevention and minimal immune rejection, while achieving high volumetric energy density in a very small space. Conventional liquid-electrolyte lithium batteries have struggled to combine high safety with high energy density, posing a barrier to clinical adoption.
The battery uses an anode-free design, a customized form factor and insulation-dam technology. In a titanium-cased button cell measuring 23 mm in diameter and 4 mm thick, it achieves a volumetric energy density of 1,045 Wh/L, 40% higher than conventional liquid-electrolyte batteries, according to EVE Energy. The company says the design can accommodate more signal-collection channels within the limited space available in the skull, extend operating time and enable smaller devices that may reduce surgical trauma. Replacing liquid electrolyte with a solid electrolyte also eliminates the risks of leakage and thermal runaway associated with liquid electrolytes, according to the company.
At the event, EVE Energy signed strategic cooperation agreements with Jingyu Medical and Sichuan Provincial People's Hospital. The partners plan to connect research and development, industrialization and clinical application to support the broader clinical use of implantable BCIs.
Sodium-ion batteries designed for electric two-wheelers
EVE Energy has also introduced a sodium-ion battery solution specifically designed for electric two-wheelers, targeting industry challenges such as short battery life, performance degradation during storage, reduced range at low temperatures and safety limitations.
The company highlights four claimed advantages of the solution:
Long cycle life: Cell cycle life reaches up to 10,000 cycles. Based on one charge every two days, EVE Energy estimates a service life of more than 25 years, potentially matching the lifespan of the vehicle.
Wide operating temperature range: The battery supports discharge temperatures from -40°C to 60°C. At -20°C, its discharge capacity retention rate exceeds 93%.
Storage stability: After being stored for one year in a fully discharged state, the battery retains a capacity recovery rate of more than 98%, according to the company.
Safety: EVE Energy says the battery does not catch fire or explode under puncture, cutting or crushing tests, and does not undergo thermal runaway under overcharging or short-circuit conditions.
Multiple technology routes support product development
The simultaneous production-line rollout of the three products marks a milestone in EVE Energy's development of advanced battery technologies. The company is advancing several technical approaches in parallel, including its Longquan solid-state series, polyoxygen all-solid-state batteries, in-situ solidification and solid-liquid batteries. These technologies are being developed for different applications, including vehicles, consumer electronics and implantable medical devices.
