Molicel’s INR-21700-P70X cell blends Li-ion energy with supercapacitor-like power for hybrids

Battery cell maker Molicel has introduced the INR-21700-P70X, the first cell in its new PX series, which the company designed to close the gap between lithium-ion batteries and supercapacitors.

The INR-21700-P70X has a capacity of 7,000 mAh and a specific energy of 340 Wh/kg, and it supports continuous discharge at 30C. Molicel rates peak power at 900 W for five seconds and says the cell can switch to peak power output in under 200 microseconds, a response time it compares to a supercapacitor that lets the vehicle handle high-frequency power pulses without fading. In a hybrid, the company says, that allows immediate current delivery during overtaking and power absorption during heavy regenerative braking.

Molicel is aiming the cell at the hybrid market. Hybrids approached a 20% share of new vehicle sales in the US in 2025, according to CNBC, and captured a 24% market share in Europe, based on International Council on Clean Transportation data.

Unlike a BEV, which runs deep daily cycles, a hybrid subjects its cells to hundreds of thousands of rapid, shallow fluctuations. To mimic that duty, Molicel tested the PX series under a supercapacitor-like profile (+10C for 10 seconds / −2C for 110 seconds, 83° C cut-off) and says the cell retained 96% of its capacity after 1,000,000 cycles.

Molicel says the cell passed UL9540A thermal runaway evaluation, that a single-crystal material cuts exothermal heat release by nearly 50% compared with conventional poly-crystal materials, and that its cells smoke rather than venting all at once, which delays and isolates thermal spread. The same containment behavior is valued in data center battery backup units (BBUs).

“By blending supercapacitor-like responsiveness with the high energy density of lithium-ion, we are redefining what hybrid powertrains can achieve in terms of raw power, safety and lifespan,” said Casey Shiue, President of Molicel.

Source: Molicel