Understanding the Tier 2 EV Battery Supply Chain
Between the raw material miners and the headline cell makers like CATL and LG Energy Solution sits a critical but less visible layer: the tier 2 component suppliers. These companies manufacture separators, electrolytes, battery management systems, current collectors, binders, and housings that go into every lithium-ion cell and pack. For procurement teams at tier 1 suppliers and OEMs, mapping this layer is essential for supply chain resilience and cost optimization.
Separators: A Concentrated Market
Battery separators—thin membranes between anode and cathode—represent one of the most technically demanding components. The market was long dominated by Japanese firms like Asahi Kasei (via its Celgard subsidiary) and Toray Industries, but China’s SEMCORP (Shanghai Energy New Materials) has taken the global volume lead, supplying CATL, BYD, LG Chem, and Samsung SDI. In North America, ENTEK secured a $1.2 billion DOE loan to build a new separator plant in Terre Haute, Indiana, signaling a push toward domestic sourcing.
Electrolytes: Chemistry Matters
Electrolyte formulation directly affects cell performance, safety, and cycle life. Shenzhen Capchem Technology, listed on the Shenzhen Stock Exchange, is one of the world’s largest producers of lithium-ion electrolyte, with production bases across China, Poland, and the United States. Other key players include Mitsubishi Chemical, UBE Industries, and BASF, each competing on additive packages tailored to NMC, LFP, and emerging solid-state chemistries.
Battery Management Systems
BMS hardware and software ensure safe charging, discharging, and thermal management. Semiconductor giants Texas Instruments and Analog Devices supply the monitor ICs, while specialized firms like Nuvation Energy and Sensata Technologies deliver complete BMS solutions. TI notably achieved the first ASIL-D rated BMS product, a milestone for automotive functional safety.
Emerging Supplier Dynamics
Several trends are reshaping tier 2 supply:
- Regionalization
- IRA incentives and EU battery regulation are driving separator and electrolyte plants closer to cell gigafactories in North America and Europe.
- Solid-state readiness
- Companies like Solid Power are developing sulphide-based solid electrolytes that could displace liquid electrolyte suppliers entirely.
- Vertical integration pressure
- Cell makers like CATL and BYD increasingly produce their own separators and electrolytes in-house, squeezing independent tier 2 margins.