Salt instead of lithium: a sodium battery built to last 15,000 cycles for the grid

The batteries that store electricity for the power grid have a different job than the ones in an electric car. A car needs to pack as much energy as possible into a small, light pack, which is why lithium dominates there. A grid battery, sitting in a field next to a solar farm, cares far less about weight and far more about lasting a long time, staying safe, and being cheap. On July 16, 2026, the world's largest battery maker, CATL, leaned hard into that distinction, and Electrek reported the launch of its new sodium-ion system, Tener Sodium.

Sodium is one of the most abundant elements on Earth — the same element in ordinary table salt — and roughly a thousand times more plentiful than lithium. That abundance makes sodium-ion cells inherently cheaper to source and free from the supply-chain squeeze around lithium. The trade-off has always been energy density, but for stationary grid storage that hardly matters. What matters is exactly what CATL is promising: Tener Sodium is rated for 15,000 charge-discharge cycles and a 25-to-30-year service life.

“A car needs to pack as much energy as possible into a small, light pack, which is why lithium dominates there.”

The durability figures go further. The system is designed to retain more than 92% of its capacity even at a frigid −20°C, and to keep going past 10,000 cycles at a sweltering 45°C — a temperature tolerance that lithium chemistries struggle to match. CATL has also cut the system's self-consumption rate, the energy it quietly burns just sitting idle, to around 1%. To scale it up, the company signed a deal with the Dutch firm Alfen to deploy 5 gigawatt-hours of Tener Sodium systems across Europe, with rollouts beginning in 2027.

Why this is genuinely good news comes down to the shape of the clean-energy transition. Solar and wind are now cheap, but they are intermittent, so the world needs vast, affordable banks of storage to soak up power when the sun shines and release it after dark. A battery chemistry that is abundant, safe, cold-tolerant and built to run for decades is close to ideal for that role.

None of this means lithium is going away — for cars, its energy density is still unmatched. But a serious, mass-manufacturable sodium alternative easing the pressure on grid storage is a quietly transformative development. It means cleaner electricity can be stored more cheaply, in more places, using a material as common as salt.