Biwatt Technology Co., Ltd. (BIWATT), a sodium-ion chemistry-based battery cell maker, presented its latest battery lineup for residential and commercial & industrial (C&I) energy storage system (ESS) applications at SNEC 2026.
The company developed its Na-ion battery, PowerNest R5, to meet key residential ESS requirements, including modularity, scalability, and intelligent battery state-of-charge (SoC) balancing. In contrast, the company’s PowerLake I3 series battery offers deployment flexibility and scalability for C&I applications.
The former product consists of a 4.5 kWh Na-ion battery unit with a maximum charging/discharging current of 55 A. After stacking 4 modular units, the cumulative storage capacity reaches 18 kWh, with a corresponding maximum current of 220 A (4 × 55 A). According to the company’s product datasheet, up to 4 stacks can be connected in parallel, with a scaled storage capacity of 72 kWh, matching residential consumers’ demands and inverter capacities. These have a built-in voltage optimizer that automatically maintains SoC balance between cells.
The PowerLake I3 is equipped with a Na-ion battery unit with a higher storage capacity of up to 8.72 kWh. This system can be deployed both indoors and outdoors. For indoor use, these units can be stacked like an individual DC cluster. The cluster size can range from 43.6 kWh (connecting 5 units on top of each other) to 130.8 kWh by connecting 15 units, as shown in the image below.
The system’s cumulative storage capacity can be expanded to up to 654 kWh by connecting 5 clusters in parallel. It allows a maximum charge or discharge current of 170 A.
In outdoor installations, up to 130.8 kWh of storage capacity is squeezed into a 1,144 × 2,172 × 1,260 mm (W × H × D) cabinet. Up to 16 cabinets can be connected in parallel to expand the total storage capacity to 2.092 MWh within an operating voltage range of 180 to 980 V (DC).
Both batteries have a guaranteed life of up to 8,000 cycles.
Separately, the company recently introduced its rack-mounted PowerNest R2 and stackable PowerNest R3 sodium-ion batteries. These are currently in mass production and commercially available worldwide.
