"Made in Tennessee" describes where the vehicle was assembled. It does not describe where the materials inside it came from, or what it costs to import those materials into the United States.
The structural problem is not unique to China. Any material originating in a country subject to elevated tariffs — whether through anti-dumping measures, executive trade actions, or bilateral trade disputes — creates the same hidden liability. China is today's dominant example. The framework applies wherever geopolitics and tariff policy intersect.
The Battery Cell Problem
Blog 1 in this series established the T1 Blindspot: Chinese-origin materials embedded inside a German-assembled component, imported into the US at a rate that reflects the assembly location rather than the material content. Blog 4 is a step further. The vehicle is assembled in Tennessee. The battery cells are assembled in Georgia. The Chinese-origin exposure is inside the cell — at the anode material level, two processing steps removed from the US plant that produced the finished product.
The anode in a lithium-ion NMC battery cell is primarily natural graphite. An EV battery pack contains approximately 60 kg of graphite per vehicle — the precise figure varies by cell chemistry and pack size, but 60 kg is the mid-range estimate for an NMC 811 cell configuration. China processes more than 90% of global battery-grade graphite supply (CSIS, DoE Critical Materials Assessment). The processing steps — purification, spheronisation, coating — require capital-intensive facilities that took years to build and that currently exist at scale almost exclusively in China.
The commodity value of battery-grade processed graphite is approximately $5/kg. The tariff rate on Chinese-origin graphite (HS 3801.10) is 93.5% — composed of anti-dumping duties, Section 301, and IEEPA stacked. This is the highest rate of any EV material in the current regime.
The calculation — Battery graphite
| Step | Working | Result |
|---|---|---|
| Graphite per vehicle | 60 kg × $5/kg | $300 customs value |
| Conservative tariff (Chinese origin, undocumented) | $300 × 93.5% | $280.50 per vehicle |
| Annual programme exposure | $280.50 × 150,000 units | $42.075M per year |
| Attestation cost | Fixed | ~$50,000 |
The $42.075M figure applies when origin is undocumented and conservative scoring is applied. It is not the expected liability — it is what sits on the balance sheet until attestation resolves it one way or the other. If Chinese-origin processing is confirmed, the liability is real. If third-party trade monitoring platform records confirm processing outside China, conservative scoring is released and the confirmed rate applies.
The SK On Georgia Complication
SK On operates a battery cell manufacturing plant in Commerce, Georgia — the confirmed supplier of NMC 811 cells for the VW ID.4 assembled in Chattanooga. The cells are US-assembled. The cathode and anode materials inside them are not necessarily US-origin.
More than 90% of Korean cathode precursor production used Chinese-origin materials as of March 2025 (SNE Research via KED Global, June 2025). That is an industry-level figure for Korea as a whole. The origin status of SK On's specific Georgia plant supply warrants investigation — which is precisely what ECC enables. The blog cannot and does not state that SK On Georgia cells contain Chinese-origin graphite as a confirmed fact. What it can state is that at industry-level concentration of 90%+ Chinese processing, the conservative scoring position is the only defensible default until supplier attestation or third-party trade records confirm otherwise.
This is the geometry of the problem. A vehicle assembled in Tennessee. Battery cells assembled in Georgia. Anode graphite with undocumented processing origin. Section 301 and IEEPA do not care that the vehicle was assembled domestically. They fire at the US border when the battery cell — the imported component — crosses from Korea or when the graphite-containing materials enter the US supply chain. The liability attaches to the imported input, not the final assembly location. The US importer of record carries the exposure. The Tennessee assembly line does not dissolve it.
A Second Regime: Silicon Steel
The graphite story sits inside the battery. The silicon steel story sits inside the motor stator — and it operates under a different tariff regime entirely, which is the point.
The stator laminations in a permanent magnet traction motor are made from grain-oriented electrical steel (GOES) — silicon steel processed to extremely tight dimensional tolerances, typically 0.20–0.27mm sheet thickness, to minimise eddy current losses at EV motor operating frequencies. HS codes 7225.11 and 7226.11 cover the flat-rolled silicon steel products used in these applications. China has invested heavily in GOES production capacity at the thinness required for EV motor laminations. It is not a geographic concentration story the way NdFeB is — it is a processing capability story. The facilities that can produce EV-grade GOES at scale are predominantly Chinese.
The tariff regime is different from the battery materials. Silicon steel carries Section 232 (steel, 25%) plus IEEPA (25%) — a 50% stacked rate. Not Section 301. Not rare earth. A different legal instrument, a different policy rationale, the same documentation gap.
The calculation — Silicon steel
| Step | Working | Result |
|---|---|---|
| Silicon steel per motor | ~30 kg × $2.50/kg (mid-range) | $75 customs value |
| Conservative tariff (Chinese origin, undocumented) | $75 × 50% | $37.50 per vehicle |
| Annual programme exposure | $37.50 × 150,000 units | $5.625M per year |
$5.625M per year from one material in one motor, under one tariff regime. Smaller than graphite. Smaller than NdFeB. Additive to both.
The Additive Exposure Argument
Each material in the EV stack carries its own tariff exposure, under its own regime, from its own supply chain dependency. They do not cancel each other out. They add.
| Material | HS Code | Regime | Exposure/vehicle | Annual (150K units) |
|---|---|---|---|---|
| Battery graphite (anode) | 3801.10 | ADD + S301 + IEEPA | $280.50 | $42.075M |
| Silicon steel (stator laminations) | 7225.11 / 7226.11 | S232 + IEEPA | $37.50 | $5.625M |
| Combined (these two materials) | $318.00 | $47.7M | ||
Add the NdFeB exposure from Blog 1 — $213 per vehicle, $31.95M per year — and the combined conservative tariff exposure across three material streams in one vehicle programme reaches $531 per vehicle and $79.65M per year.
Three materials. Three tariff regimes. One vehicle. All of it undocumented until ECC traces it.
§ 1592 Penalty Scenario. If CBP conducts a focused assessment and determines that Chinese-origin content was systematically under-declared across a vehicle programme — covering battery graphite, silicon steel, and NdFeB simultaneously — the maximum penalty under 19 U.S.C. § 1592(c) for gross negligence is up to 4× unpaid duties across all material streams and all prior import periods within the statute of limitations. On $79.65M in annual duty liability, the 4× ceiling is not a theoretical calculation. It is the number that belongs in the conversation between the trade compliance team and in-house legal — and the reason that conversation should happen before CBP opens a focused assessment, not after. The prior disclosure provision under 19 CFR 162.74 reduces that ceiling to interest on underpaid duties only — but solely if filed before CBP initiates an investigation.
Where ECC Fits
ECC does not claim to know the confirmed origin of SK On Georgia's graphite supply or the specific provenance of the silicon steel in any particular motor stator. The correct framing is the one that applies throughout this series: ECC builds the starting point from publicly available production route data, industry-level origin concentration figures, and third-party trade monitoring platform records. That baseline provides the conservative scoring position. Suppliers validate, correct, and confirm — moving nodes from conservative inference to supplier-declared or fully attested states.
The difference between a compliance team that starts from a blank spreadsheet and one that starts from ECC's material baseline is not research effort. It is months of work and the difference between a proactive prior disclosure and a reactive response to a CF-28 that arrived without warning.
"Made in Tennessee" is accurate. It is also incomplete. ECC completes it.
Download the T1 Blindspot One-Pager [Asset 1] and the CFO Brief [Asset 2] for the full material depth diagram, the tariff scoring state model, and the financial scenario comparisons across conservative and attested scoring positions.
View T1 Blindspot One-Pager → View CFO Brief →