Finding
Everything above the cell is Tesla-made; the cells come from CATL, BYD and EVE until LG Energy Solution Lansing ships
The ring holds 19 supplier rows across six layers: nine in-house, one sole source, eight China-supplied and five with the supplier not disclosed.
Everything above the cell is in-house: modules, BMS, inverter, heat-pump thermal system, the Megablock transformer, software and all three Megafactories (Brookshire, Lathrop, Shanghai). The cell layer is the China dependence: CATL was the sole storage-cell supplier through 2023, FinDreams (BYD) is second source for Shanghai, EVE ships from Malaysia, and even the in-house Nevada LFP line runs on CATL equipment. LG Energy Solution in Lansing, Michigan is the only non-Chinese cell source, and only from August 2027; LFP cathode and graphite sources are undisclosed and almost certainly Chinese.
The ring
Who supplies each layer
In-house rows first in each layer, then sole, primary, second and multi-source suppliers. The left border shows the supplier country: red China, gold Japan, Korea or Taiwan, blue the US and Europe, gray not disclosed. Confidence: confirmed (company or filing), reported (credible press), inferred (deduced, not disclosed).
| Supplier | Component | Country | Plant or location | Relationship | Confidence | Evidence and links |
|---|---|---|---|---|---|---|
| Cells | ||||||
| Tesla (Gigafactory Nevada LFP cell line) Parent: Tesla | LFP prismatic cells for Megapack (in-house line) About 10 GWh a year target; early ramp confirmed April 2026 per press; output goes mainly to Megapack | US | Sparks, Nevada, US | in-house | reported | press report |
| CATL | LFP cell production equipment for the Nevada line Tesla bought idle CATL LFP line equipment; the US in-house line rests on Chinese process tooling | China | China (equipment origin) | sole source | reported | press report (Bloomberg via Yole) |
| CATL | LFP storage cells (Megapack 2 XL; Shanghai Megafactory and US imports) Sole Tesla ESS cell supplier through 2023 and primary for Shanghai; Tesla CFO said in July 2025 that the energy business relies on Chinese LFP supply | China | China (plants not disclosed) | primary | reported | press report (LatePost via CnEVPost) |
| FinDreams Battery (BYD) Parent: BYD | LFP storage cells for Shanghai Megafactory Over 20% of Shanghai Megapack orders from Q1 2025 (up to about 8 GWh a year); brought in to gain leverage on CATL | China | China (plant not disclosed) | second source | reported | press report (LatePost via CnEVPost) |
| EVE Energy | LFP storage cells for Tesla US Supply to Tesla US expected from 2026; EVE filing named only a customer in the Americas; Chinese-owned plant outside China | China | Kulim, Malaysia | second source | reported | press report (LatePost via CnEVPost) |
| LG Energy Solution Parent: LG | 2.8-liter prismatic LFP cells for Megapack 3 $4.3 billion, August 2027 to July 2030 with extension options; confirmed by the US government, neither company has commented; Tesla cell engineers co-designed the 2.8-liter cell | South Korea | Lansing, Michigan, US | multi-source | confirmed | government release |
| not disclosed | LFP cathode active material No disclosed source for Nevada or imported cells; candidates Hunan Yuneng, Shenzhen Dynanonic, Hubei Wanrun (all China) - inferred; no US LFP cathode at scale | China | China | multi-source | inferred | none found |
| not disclosed | Graphite anode material Candidates BTR, Shanshan, Putailai (all China) - inferred; graphite is the hardest LFP input to source outside China | China | China | multi-source | inferred | none found |
| Pack and BMS | ||||||
| Tesla | Battery modules, BMS and pack integration Larger module; busbar connections cut from 24 to 3; Tesla designs the BMS (Megapack data sheet not public) | US | Brookshire, Texas; Lathrop, California; Shanghai, China | in-house | reported | press report BESS Products |
| Thermal | ||||||
| Tesla | Thermal management system (derived from Model Y heat pump) Simplified heat pump design with 78% fewer connections | US | Megafactories | in-house | reported | press report |
| not disclosed | Valves, pumps and compressors Candidates Sanhua and Tuopu (China, with Mexico plants), Tesla heat-pump valve suppliers on vehicles - inferred | multi-source | inferred | none found EV Thermal Management Systems | ||
| Power electronics and SiC | ||||||
| Tesla | Integrated bidirectional inverter Standard configuration includes an integrated inverter; no outside supplier named | US | Megafactories | in-house | reported | press report BESS Products |
| Tesla | Megablock medium-voltage transformer Tesla said it will build its own transformers to avoid multi-year utility transformer lead times | US | Brookshire, Texas, US | in-house | reported | press report Grid Equipment Supply Chain |
| not disclosed | Inverter power semiconductors (IGBT or SiC) Candidates Infineon, STMicroelectronics, onsemi (Tesla vehicle power-device suppliers) - inferred; no teardown of Megapack 3 | multi-source | inferred | none found EV Power Semiconductors | ||
| not disclosed | Megablock medium-voltage switchgear Pre-integrated on the skid; maker not named; candidates Schneider Electric, Eaton, Siemens, ABB, Hitachi Energy - inferred | multi-source | inferred | none found Tesla Megablock | ||
| Software and autonomy | ||||||
| Tesla | Autobidder, Opticaster, Powerhub and site controls Trading and dispatch software sold with Megapack | US | in-house | confirmed | company release Tesla Autobidder and Opticaster | |
| Final assembly | ||||||
| Tesla Megafactory Houston Parent: Tesla | Megapack 3 and Megablock assembly 50 GWh a year planned; production started 2026, deliveries from late 2026 | US | Brookshire, Texas, US | in-house | confirmed | press report BESS Products |
| Tesla Megafactory Lathrop Parent: Tesla | Megapack 2 XL assembly About 40 GWh a year | US | Lathrop, California, US | in-house | confirmed | press report BESS Products |
| Tesla Shanghai Megafactory Parent: Tesla | Megapack assembly for export markets About 40 GWh a year; cells from CATL and FinDreams; Megapack 3 output there not confirmed | US | Lingang, Shanghai, China | in-house | confirmed | press report BESS Products |
Sources
Sources and scope
- Scope
- Tesla Megapack 3 / Megablock supplier ring
- Sources
- ElectronsX flagship machine ring dataset: teardowns, company releases and filings, supplier disclosures and trade press; one source per row
- Updated
- 2026-10