Custom 12V 40Ah Sodium Ion Start-Stop Battery (H7)

A 12V 40Ah sodium-ion starting battery for engine cranking and start-stop duty, replacing lead-acid in a smaller, lighter envelope. It carries 480 Wh of usable energy and delivers 120A continuous — a full 3C draw, with headroom for the surge loads motive duty demands.

Charging at 40A brings it to full in roughly 1.5 hours. The operating window is -40~80°C on discharge and -20~50°C on charge. The pack measures 318 x 176 x 187 mm (Group Size H7) and weighs 7 kg.

Where it sits in the range

Within our 12V range this sits between the 30Ah and 42Ah builds. If your runtime target is tighter than expected once we model the duty cycle, the 42Ah configuration is the usual next step; if weight or envelope is the binding constraint, the 30Ah build is lighter.

What we customise

Case format, terminal position and polarity, cranking rating and cold-weather behaviour are specified per platform. BMS communication over CAN or RS485 is available where the vehicle expects it, with Bluetooth for diagnostics.

Common questions

Will it work with our existing alternator and charging system?
In most cases, but voltage regulation matters. Send the charging voltage range and we confirm compatibility.

How does it behave in cold weather?
Charging is limited at low temperature, which is the main difference from lead-acid. Tell us your minimum ambient and we discuss heating or chemistry options.

Cells, compliance and lead time

Grade A sodium-ion cells from qualified suppliers. Every pack ships with a UN38.3 test summary and MSDS prepared for air, sea and road transport. Assembly and testing take around 7 working days. Cell supply is what sets the overall schedule: when the cells your design needs are in stock, samples ship in 12–15 working days; when they have to be sourced, allow 20–25. Tell us your target date early and we will confirm cell availability before you commit to it. Production runs 30–35 working days. There is no minimum order quantity — this is a custom design business and we quote single units, with pricing improving noticeably from 100 packs upward. Sodium-ion is a developing line for us, so warranty terms are agreed per project.