UNIGRID unveils 9.25-kWh sodium-ion battery for residential applications

A company called UNIGRID has started shipping its first home battery, called Na+Casa, to U.S. customers. Unlike most home batteries on the market, it uses sodium-ion chemistry instead of lithium-ion. The battery is rated at 9.25 kWh of storage capacity and is designed to last 25 years. It's built to work with most existing hybrid inverters, which the company says makes it easier to add to a solar setup you already have without swapping out other equipment.

The main selling point of sodium-ion chemistry is safety and durability rather than performance. Because it has no lithium, UNIGRID says the battery cannot experience thermal propagation, the chain reaction that can cause lithium batteries to overheat and catch fire. It's also rated to operate across a wide temperature range, from -40°F to 140°F, so the company is pitching it as a good fit for homes in places with harsh winters, extreme heat, or unpredictable weather. Sodium is also more abundant than the lithium, cobalt, and nickel used in typical batteries, which UNIGRID argues could make supply chains more stable over time.

For homeowners weighing a battery to pair with solar panels or to back up power during outages, this adds a new chemistry option to consider alongside standard lithium-ion systems, with claims of longer lifespan and broader temperature tolerance. No pricing was given.