Vietnam’s first Kim Long-BYD battery plant opens at US$135 million
7 Jul 20266 min read
Summary
- Kim Long Motor Hue and BYD Battery broke ground on a US$135 million electric vehicle battery joint venture in central Vietnam in early 2026, designed to deliver 80 per cent localisation for Kim Long Motor.
- The plant fits the China+n manufacturing thesis in an electric vehicle context, while VinFast operates a competing captive supply chain out of Hai Phong.
- Beyond the US, the batteries will be tested by the EU's battery passport regime and by Thailand, the Philippines and Indonesia as those markets scale electric vehicle demand.
Kim Long Motor Hue and China’s BYD Battery broke ground on a US$135 million electric vehicle battery joint venture in Hue province, central Vietnam, in early 2026, the largest single battery manufacturing commitment Vietnam has secured outside the established VinFast supply chain. The plant is structured to deliver 80% localisation for Kim Long Motor’s commercial vehicle range by the second quarter of 2026, with BYD providing technology transfer and Kim Long Motor investing and operating. The US$135 million commitment is a mid-scale plant by regional battery-industry standards, at roughly one-tenth the size of the largest gigafactory investments in Thailand and Indonesia, but the largest single-site commercial-vehicle battery investment in Vietnam to date. The investment is the headline story. The harder story sits one layer below: Vietnam is absorbing Chinese battery overcapacity at the exact moment Washington has opened a Section 301 investigation aimed at exactly that pattern.
Vietnam’s electric vehicle supply chain has grown faster than its tariff exposure to the United States has stabilised. VinFast, the Hai Phong-headquartered electric vehicle manufacturer that is Vietnam’s largest passenger-EV brand, has built its own battery production line through subsidiaries. Outside VinFast, the battery manufacturing capacity has lagged the vehicle assembly capacity, with most Vietnamese assemblers importing cells from China, Korea or Japan. The Kim Long-BYD plant closes that gap on the commercial vehicle side. Phase 1 covers 4.4 hectares of land with a designed capacity of 3 gigawatt-hours per year, focused on lithium iron phosphate cells for trucks, buses, minivans and minibuses, per Vietnam-based business publication The Investor. Phase 2 expands the site to 10 hectares and lifts total capacity to 6 gigawatt-hours, adding lines for passenger vehicles.
The partnership structure matters because it sits inside a specific policy gap. BYD provides battery cell technology and process engineering; Kim Long Motor provides the investment, the land, the Vietnamese workforce and the operational permit. The output is sold in Vietnam under Kim Long Motor branding, qualifying as Vietnamese-manufactured for domestic regulatory and tariff purposes. For Chinese battery producers facing oversupply at home and tariff barriers in the US and Europe, this kind of joint-venture localisation in Vietnam is the operational answer to a margin problem. The Chinese press has been clear about the strategic intent. The Vietnamese press has been clear about the investment volume. The third reading sits in Washington.
The US Trade Representative opened a Section 301 investigation into Chinese industrial excess capacity earlier in 2026. The probe specifically targets sectors where Chinese subsidised production has built capacity well beyond domestic demand, with EV batteries identified as one of the load-bearing categories. Vietnam sits inside the broader tariff-scrutiny picture through both the Section 301 probe and a parallel line of Southeast Asia trade actions the USTR has moved on through 2025 and 2026, with the exact scope of forced-labour and country-specific measures still being defined. The combination matters for the Kim Long-BYD plant in a specific way: the cells produced in Hue will be physically Vietnamese, but the underlying battery chemistry, process technology and capital structure trace back to BYD. If the Section 301 probe results in tariff treatment that follows the substantive technology origin rather than the formal manufacturing location, the Kim Long-BYD output faces a tariff exposure that the joint-venture structure was meant to avoid.
Three operational implications flow from this for buyers of Vietnamese-assembled commercial vehicles and for the wider Asian EV supply chain. The first is contract architecture. Buyers committing to multi-year supply agreements with Vietnamese commercial vehicle makers need indemnification language covering future US tariff treatment of Chinese-origin technology, with explicit definitions of what counts as Chinese origin. The second is geographic concentration. The China+n diversification thesis that drove battery manufacturing into Vietnam, Thailand, Indonesia and Malaysia is now operating against a US tariff framework that may not accept the diversification as substantive. The third is the substitution question. If Chinese-technology batteries assembled in Vietnam face the same tariff treatment as Chinese-origin batteries, the Section 301 probe collapses the entire China+n battery localisation thesis back to a country-of-origin question that the joint-venture structure was specifically designed to engineer around.
For Vietnam itself, the Kim Long-BYD plant is a foreign direct investment win with a measurable industrial development dividend. The 4.4-hectare Phase 1 site will employ several hundred workers at production wages well above the regional manufacturing average, and the technology transfer commitment from BYD creates a domestic capability that Vietnamese state policy has been working toward for half a decade. The downside risk runs through the export-share of the production. Domestic Vietnamese demand for commercial vehicle batteries will absorb most of Phase 1 output.
The market question for Phase 2 is why the US-tariff exposure matters at all when Europe, Thailand and other regional markets could absorb the passenger-vehicle output. The answer runs through margin pool rather than volume pool. European buyers face their own EU-level tariff on Chinese-technology EVs and battery cells introduced in 2024, which prices Vietnamese-Chinese joint-venture output at a comparable premium to direct Chinese exports. Thai and other ASEAN commercial-vehicle buyers absorb Vietnamese-assembled trucks and buses in meaningful volume, but at lower price points and thinner margins than the US market historically pays. The US commercial-vehicle market is the largest single margin pool available to Kim Long Motor’s Phase 2 output, which is why the Section 301 exposure disproportionately shapes the project’s return profile even when the US will not take most of the volume. The Phase 2 expansion into passenger-vehicle batteries shifts the export-dependence question into a different category, with US-bound shipments the most margin-exposed even where they are not the largest by unit count.
The next twelve months will surface the answer. The Section 301 investigation timeline runs through Q4 2026, with proposed tariff schedules expected in early 2027. Vietnam’s own bilateral negotiation track with the United States is open but unresolved. Kim Long Motor and BYD have committed the capital and the technology; the regulatory environment in which the plant operates is still being built.
When the first batch of Kim Long-BYD batteries leaves the Hue plant for installation in a Vietnamese-assembled bus or truck destined for export, the question is whether the country-of-origin label is enough to clear US customs, or whether the trade probe currently underway redefines what country-of-origin means for technology-transfer joint ventures across Asia.
Vietnam’s electric vehicle supply chain has grown faster than its tariff exposure to the United States has stabilised. VinFast, the Hai Phong-headquartered electric vehicle manufacturer that is Vietnam’s largest passenger-EV brand, has built its own battery production line through subsidiaries. Outside VinFast, the battery manufacturing capacity has lagged the vehicle assembly capacity, with most Vietnamese assemblers importing cells from China, Korea or Japan. The Kim Long-BYD plant closes that gap on the commercial vehicle side. Phase 1 covers 4.4 hectares of land with a designed capacity of 3 gigawatt-hours per year, focused on lithium iron phosphate cells for trucks, buses, minivans and minibuses, per Vietnam-based business publication The Investor. Phase 2 expands the site to 10 hectares and lifts total capacity to 6 gigawatt-hours, adding lines for passenger vehicles.
The partnership structure matters because it sits inside a specific policy gap. BYD provides battery cell technology and process engineering; Kim Long Motor provides the investment, the land, the Vietnamese workforce and the operational permit. The output is sold in Vietnam under Kim Long Motor branding, qualifying as Vietnamese-manufactured for domestic regulatory and tariff purposes. For Chinese battery producers facing oversupply at home and tariff barriers in the US and Europe, this kind of joint-venture localisation in Vietnam is the operational answer to a margin problem. The Chinese press has been clear about the strategic intent. The Vietnamese press has been clear about the investment volume. The third reading sits in Washington.
The US Trade Representative opened a Section 301 investigation into Chinese industrial excess capacity earlier in 2026. The probe specifically targets sectors where Chinese subsidised production has built capacity well beyond domestic demand, with EV batteries identified as one of the load-bearing categories. Vietnam sits inside the broader tariff-scrutiny picture through both the Section 301 probe and a parallel line of Southeast Asia trade actions the USTR has moved on through 2025 and 2026, with the exact scope of forced-labour and country-specific measures still being defined. The combination matters for the Kim Long-BYD plant in a specific way: the cells produced in Hue will be physically Vietnamese, but the underlying battery chemistry, process technology and capital structure trace back to BYD. If the Section 301 probe results in tariff treatment that follows the substantive technology origin rather than the formal manufacturing location, the Kim Long-BYD output faces a tariff exposure that the joint-venture structure was meant to avoid.
Three operational implications flow from this for buyers of Vietnamese-assembled commercial vehicles and for the wider Asian EV supply chain. The first is contract architecture. Buyers committing to multi-year supply agreements with Vietnamese commercial vehicle makers need indemnification language covering future US tariff treatment of Chinese-origin technology, with explicit definitions of what counts as Chinese origin. The second is geographic concentration. The China+n diversification thesis that drove battery manufacturing into Vietnam, Thailand, Indonesia and Malaysia is now operating against a US tariff framework that may not accept the diversification as substantive. The third is the substitution question. If Chinese-technology batteries assembled in Vietnam face the same tariff treatment as Chinese-origin batteries, the Section 301 probe collapses the entire China+n battery localisation thesis back to a country-of-origin question that the joint-venture structure was specifically designed to engineer around.
For Vietnam itself, the Kim Long-BYD plant is a foreign direct investment win with a measurable industrial development dividend. The 4.4-hectare Phase 1 site will employ several hundred workers at production wages well above the regional manufacturing average, and the technology transfer commitment from BYD creates a domestic capability that Vietnamese state policy has been working toward for half a decade. The downside risk runs through the export-share of the production. Domestic Vietnamese demand for commercial vehicle batteries will absorb most of Phase 1 output.
The market question for Phase 2 is why the US-tariff exposure matters at all when Europe, Thailand and other regional markets could absorb the passenger-vehicle output. The answer runs through margin pool rather than volume pool. European buyers face their own EU-level tariff on Chinese-technology EVs and battery cells introduced in 2024, which prices Vietnamese-Chinese joint-venture output at a comparable premium to direct Chinese exports. Thai and other ASEAN commercial-vehicle buyers absorb Vietnamese-assembled trucks and buses in meaningful volume, but at lower price points and thinner margins than the US market historically pays. The US commercial-vehicle market is the largest single margin pool available to Kim Long Motor’s Phase 2 output, which is why the Section 301 exposure disproportionately shapes the project’s return profile even when the US will not take most of the volume. The Phase 2 expansion into passenger-vehicle batteries shifts the export-dependence question into a different category, with US-bound shipments the most margin-exposed even where they are not the largest by unit count.
The next twelve months will surface the answer. The Section 301 investigation timeline runs through Q4 2026, with proposed tariff schedules expected in early 2027. Vietnam’s own bilateral negotiation track with the United States is open but unresolved. Kim Long Motor and BYD have committed the capital and the technology; the regulatory environment in which the plant operates is still being built.
When the first batch of Kim Long-BYD batteries leaves the Hue plant for installation in a Vietnamese-assembled bus or truck destined for export, the question is whether the country-of-origin label is enough to clear US customs, or whether the trade probe currently underway redefines what country-of-origin means for technology-transfer joint ventures across Asia.