320Ah Sodium-Ion Battery: Rept Battero's Long-Duration Storage Breakthrough
At SNEC 2026 in Shanghai, Chinese battery manufacturer Rept Battero unveiled a product that could reshape the long-duration energy storage landscape: the Wending 320Ah sodium-ion battery cell. Designed specifically for utility-scale storage projects and extreme climate applications, this cell represents one of the most ambitious sodium-ion products targeting the grid storage market to date.
Technical Specifications That Demand Attention
The Wending 320Ah sodium-ion battery cell brings impressive performance metrics to the table. Rated at 320 ampere-hours, the cell achieves a cycle life exceeding 20,000 cycles and maintains a round-trip efficiency of at least 97%. Perhaps most striking is its operating temperature range: from -50°C to 60°C, making it one of the widest-temperature batteries available for grid-scale applications.
At the extreme low end of -50°C, the cell reportedly retains more than 87% of its rated capacity — a performance characteristic that would make it viable for deployment in the coldest regions of northeastern and northwestern China, as well as Nordic countries and Canada. The design service life of 25 to 30 years aligns with the expected operational lifespan of utility-scale battery storage assets, meaning project developers can plan for full lifecycle value.
Wending Architecture: Rethinking Prismatic Cell Design
Rept Battero's Wending prismatic cell architecture is the foundation of this product. Previously deployed in the company's 314Ah and 320Ah LFP storage cells, the Wending platform is designed to increase internal space utilization, shorten current paths, and reduce internal resistance. Applying this architecture to sodium-ion chemistry represents a strategic bet that the two technologies can share a common manufacturing platform.
The sodium-ion version incorporates material-level improvements across three critical domains: cathode particle optimization for better ion transport, porous anode structures that enhance cycle stability, and electrolyte interface engineering that specifically targets low-temperature performance. These aren't incremental tweaks — they represent a systematic engineering approach to overcoming sodium-ion's traditional limitations relative to LFP. Visit our store to learn about current-generation LiFePO4 battery technology.
Sodium-Ion vs LFP: A Complementary Relationship
Rept Battero has been careful to position the 320Ah sodium-ion cell as a complement to LFP technology rather than a replacement. The company explicitly targets applications where low-temperature performance, ultra-long cycle life, and reduced exposure to raw material price volatility are particularly important. Sodium's abundance — it's the sixth most common element in Earth's crust — gives sodium-ion batteries a structural cost advantage over lithium-based chemistries, especially during periods of lithium price volatility.
The prismatic aluminum-shell format is designed for compatibility with mainstream energy storage system architectures, minimizing the need for significant pack or container redesign. This pragmatic approach should accelerate adoption among system integrators who want to offer sodium-ion options without overhauling their entire product lineup.
Safety and Market Readiness
Safety performance was a headline feature at the SNEC 2026 launch. The 320Ah sodium-ion battery cell passed both overcharge and nail-penetration tests without fire, explosion, or thermal runaway. The terminal design incorporates double insulation and double sealing to reduce electrical safety risks — features that matter enormously for utility-scale deployments where a single cell failure can cascade into catastrophic system-level events.
The cell is currently in A-sample validation, with reliability testing and customer sampling underway. Mass production and commercial deliveries are planned for 2027. Initial deployments will target renewable energy bases in northwestern China, cold-climate storage projects in northeastern China, and selected international markets following certification. For energy storage professionals evaluating long-duration technologies, the Rept Battero 320Ah sodium-ion cell deserves a spot on your watchlist.
