Leapmotor's CTC 3.0 EV Battery Eliminates the Separate 12-Volt Battery
Leapmotor's new CTC 3.0 battery system integrates low-voltage power into the main EV battery, removing the separate 12-volt battery from models due from 2027.
Leapmotor says its next generation of electric vehicles will dispense with a component that has survived the industry’s shift away from combustion engines: the separate 12-volt auxiliary battery.
The Chinese automaker unveiled its Cell-to-Chassis 3.0 High-Low Fusion Battery alongside the new LEAP 5.0 vehicle architecture at its 2026 Tech Day. Both technologies are intended for Leapmotor products arriving from 2027 onward.
According to Leapmotor’s official announcement, CTC 3.0 combines high- and low-voltage functions within the same battery system. That removes the need for a conventional standalone 12-volt battery while retaining low-voltage power for lights, screens, security systems, HVAC controls, wipers and safety equipment.
The idea sounds simple, but it changes one of the most established layers in a vehicle’s electrical architecture.
Why Electric Cars Still Use Low-Voltage Power
An EV’s large traction battery may operate at hundreds of volts, but most of the car does not need — and should not be directly exposed to — that voltage. The low-voltage system powers control modules and everyday accessories while helping the vehicle manage the hardware that connects the traction battery to the drivetrain.
That is why electric cars have continued to carry a smaller auxiliary battery even though they no longer need a 12-volt starter motor to crank an engine. Some manufacturers have replaced traditional lead-acid units with lithium-based auxiliary batteries, but the separate low-voltage supply has generally remained.
Leapmotor’s proposed solution is more radical. The company says CTC 3.0 uses the main battery’s cells and modules for both high- and low-voltage duties, with shared thermal management and energy distribution. Leapmotor claims the system delivers seven times the low-voltage capacity and functionality of its previous design.
The potential ownership benefit is straightforward: there is no separate auxiliary battery to weaken, replace or recycle. A failed 12-volt battery can immobilize an otherwise charged EV, so removing that single component could also eliminate a frustrating failure point.
However, Leapmotor has not yet published the detailed service and safety architecture behind the system. Important unanswered questions include how low-voltage power is maintained when the traction system is isolated, how roadside recovery works after a deeply discharged pack and what redundancy protects essential safety systems. Those details will matter more than the headline once production vehicles arrive.
Cell-to-Chassis Integration Goes Further
CTC 3.0 also continues the industry’s push to integrate battery hardware directly into the vehicle structure rather than treating the pack as a completely separate box.
Leapmotor describes the system as “package-less,” with battery modules integrated into the chassis. Tighter integration can reduce duplicated structure and create more usable room, but it also makes repair strategy, crash protection and long-term serviceability especially important.
The company says large-scale use could remove millions of lead-acid auxiliary batteries from the waste stream. That environmental claim depends on production volume and the complete lifecycle of the replacement electronics, but using fewer separate components is a credible engineering objective.
LEAP 5.0 Targets More Cabin Space
The accompanying LEAP 5.0 New Mobile Space Architecture is intended to underpin Leapmotor’s next product generation. The company is making unusually large space-efficiency claims for the platform.
Leapmotor says combining an all-in-one climate-control unit with a rear-mounted powertrain increases cabin length by 19 percent, reduces the component count by 18 percent and cuts required piping by 30 percent. A vertical shock-absorber layout is claimed to improve front-row lateral legroom by 37.5 percent.
The most dramatic number is a claimed 63.7-percent increase in interior height, enabled by a higher roof, a lower flat floor and a new skateboard layout. Leapmotor says the resulting loft-style cabin can provide standing height.
Those figures are manufacturer claims, and the announcement does not clearly define the previous architecture, vehicle class or measurement method used for every comparison. The first production model will give the numbers useful context. For now, they point toward a tall, space-focused vehicle rather than a conventional low-roof sedan.
The First Vehicles Arrive in 2027
Leapmotor says the first vehicles based on LEAP 5.0 will be revealed in 2027, but it has not named the models or confirmed battery capacities, driving range, charging speed or prices.
The technology is globally relevant because of Leapmotor’s relationship with Stellantis. Stellantis became a strategic shareholder in 2023, and the companies created the Stellantis-led Leapmotor International joint venture in 2024 to sell Leapmotor vehicles outside Greater China.
That connection gives Leapmotor a faster route into international markets than a standalone Chinese startup would typically have. It does not guarantee that LEAP 5.0 vehicles will reach Canada or the United States, however, and no North American launch has been announced.
The separate 12-volt battery is easy to overlook until it fails. Leapmotor’s CTC 3.0 system is interesting because it targets that mundane but persistent weakness rather than chasing only a larger range figure or a higher charging peak. If the production design proves reliable, recoverable and serviceable, the low-voltage integration could be more consequential than its modest-sounding description suggests.