Molicel

Company URL: molicel.com

Molicel is the brand of E-One Moli Energy Corp., a Taiwanese maker of high-power cylindrical lithium-ion cells owned by the Taiwan Cement Corporation (TCC) group [1]. It doesn’t compete on GWh with the big EV cell suppliers. Instead it focuses on 18650 and 21700 cells where power-to-energy ratio matters most: hypercars and race vehicles, electric motorcycles, eVTOL aircraft and drones, power tools, and backup battery units (BBUs) for data centres [1][2].

The brand has an unusually long history for a lithium cell maker. It started in a physics lab at the University of British Columbia in 1977, and Molicel describes itself as the first company to make rechargeable lithium-metal cells and the first to make lithium-ion cells in North America [1]. A materials R&D centre is still based in Maple Ridge, British Columbia, while cell production is in Taiwan.

1. Cell Technology and Product Range

Molicel groups its cells into three families [1]:

• P series (ultra-high power) – the core product line, e.g. P28A and P30B in 18650, and P42A, P45B, P50B and P60C in 21700.
• S series (safety cells) – variants aimed at BBUs and data-centre HVDC systems, some using low-flammability technology.
• M series (medium power) – higher-energy cells such as the INR-21700-M65A, which Molicel quotes at 325 Wh/kg and over 1,000 cycles.

The INR-21700-P50B is a good example of where the company positions itself. Molicel’s headline figures for it are [2]:

Compared with the older P45B, Molicel claims the P50B roughly doubles cycle life under a +1C / −100 W duty cycle, from about 700 to 1,400 cycles [2]. These are manufacturer figures; see Molicel P45B 21700 Tests for an independent look at the previous-generation cell and Molicel’s 21700 High-Power Roadmap for how the range has developed.

2. Manufacturing Footprint

Sites and roles are as listed by Molicel [1][3].

3. The 2025 Kaohsiung Fire

On 14 July 2025 a fire broke out in the formation area of the MQE plant in Kaohsiung. TCC’s one-month report concluded that defective semi-finished cells had most likely reached the room-temperature aging area of formation, either because of a lapse during manual inspection or an equipment fault during automated handling, and then went into thermal runaway, which spread to neighbouring cells. The report also says the plant’s formation-area fire suppression did not activate [3]. Fifteen people had minor injuries, and TCC put the book value of scrapped plant, equipment and inventory at about NT$16.4 billion [3].

For cell engineers the incident is a reminder that formation and aging is where a factory holds its largest stock of charged, unproven cells, so defect screening and fire detection at that stage matter as much as they do in the finished product.

1977

• Moli Energy is founded in Canada.

1987

• The MOLICEL brand is created.

1998

• E-One Moli Energy Corp. is founded in Taiwan.

2000

• E-One Moli acquires NEC Moli Energy (Canada); the first Tainan plant is completed.

2004

• Launch of what Molicel describes as the first 18650 lithium-ion cell for power tools.

2010

• A second Tainan plant is completed.

2021

• The 4.5 Ah INR-21700-P45B is launched, and ground is broken on a new gigafactory in Kaohsiung.

2022

• Molicel partners with McMurtry Automotive and is selected by Vertical Aerospace for its VX4 eVTOL.

2023

• The Kaohsiung plant is scheduled to start 21700 mass production in Q3; Molicel cells power the MotoE series from 2023.

2024

• The INR-21700-P50B enters mass production; S-series cells ship in BBUs to cloud service providers.

2025

• A fire on 14 July destroys much of the Kaohsiung plant operated by subsidiary Molie Quantum Energy (MQE); production is shifted to Tainan and overseas partners [3]. The INR-21700-P60C is announced [1].