A battery maker fixed the wheelbase on 20 October 2026, and with it the commercial vehicle axle: CATL tied its standard swap blocks to 3.8 m and 4.2 m frames, so the front axle, the drive axle and the e-axle must fit a dimension set by the battery rather than the truck maker.
Two battery blocks, two wheelbases
At its ShengSuan 2027 event in Beijing on 20 October, CATL launched the Tianxing II heavy-truck range and the Qiji swap ecosystem. The 260# block carries 432 kWh for 3.8 m wheelbase tractors; the 300# carries 513 kWh for 4.2 m. Standardising the block standardises the frame opening, and that opening decides where the e-axle and the battery sit at once.
3.2 metres becomes a front axle problem
The underfloor short-wheelbase version is in production at 3.35 m and supports 3.2 m, about 0.45 m shorter than the common 3.8 m, cutting turning radius by 0.9 m for mines, ports and mountain bends. That radius is not a frame number but a front axle number: a larger steering angle, a stronger knuckle, a re-cut steering trapezoid.
The nose gets lighter and the rating moves
The rear-mounted ultra-light pack is about 534 kg below the class average and drops the centre of gravity by 400 mm; the ultra-thin pack compresses from 860 mm to 580 mm, adding 3 cubic metres of load volume, so nine trucks do the work of ten, worth about 25,000 yuan more per truck a year. Less mass over the front axle changes its rating.
Five-minute swaps remove the service window
Qiji swaps a pack in five minutes at 99.99 percent first-attempt success, two bays serving nearly 200 swaps a day, and five trunk lines have passed 5 million km. CATL signed 13,000 trucks on the day with China Post, SF Express, YTO and STO, and plans 900 stations by the end of 2026, 2,000 in 2027 and 10,000 long term. A truck that stops five minutes instead of two hours offers no maintenance window, so long oil drains and maintenance-free wheel ends become base specification.
What this means for Yihe Axle
Zhucheng Yihe Axle Co., Ltd. reads the 260#/300# split as a product plan: front axles rated for a lighter nose but a larger steering angle, drive axles and e-axles packaged for a 3.2-4.2 m frame opening, and wheel ends built for high mileage. CATL says over 430,000 electric trucks, more than 70 percent of the fleet, run its batteries.
Bottom line
From October 2026 the commercial vehicle axle is dimensioned by the battery: a 3.2-to-4.2 m wheelbase set by standard swap blocks fixes the front axle steering angle and the e-axle package before any torque figure is chosen.
