MG Puts Semi-Solid Batteries in Its 2027 Plug-In Hybrids

Semi-solid batteries were supposed to debut in six-figure EVs. MG is putting them in plug-in hybrid SUVs priced for the family driveway, starting in 2027, and the choice of segment matters more than the chemistry does.

At its Tech Day in London, MG, the British marque under SAIC's control, unveiled a technology roadmap built around hybridisation and automated driving, headlined by a new generation of Plug-in Hybrid+ vehicles carrying semi-solid batteries and advanced driver-assistance systems from 2027. The Plug-in Hybrid+ label is doing more work here than the marketing suggests.

What MG Actually Announced at London Tech Day

Three next-generation PHEVs are confirmed: the next MG ZS in 2027, followed by the MG HS and MG S9. All three will use what MG calls SolidCore. It is built around a semi-solid-state battery architecture with a 3D spinel structure, and MG claims higher energy-conversion efficiency and faster power delivery than conventional liquid-electrolyte packs.

SolidCore is not the same thing as full solid-state. Semi-solid means the electrolyte is thickened rather than replaced, which is a real chemistry step but not the endgame the industry has been promising for a decade. The distinction matters when a manufacturer's press release blurs the two, which most of them do.

MG is not introducing the chemistry from scratch. The same semi-solid technology already debuted in China on the MG4 (Urban) Anxin EV, and MG is now extending it to the Plug-in Hybrid+ line alongside a new hybrid powertrain with a Toyota-style e-CVT. The e-CVT swap is a quieter but consequential change, MG's outgoing hybrid architecture used a simpler layout, and moving to a planetary-gear e-CVT is the powertrain equivalent of admitting Toyota has been right about hybrid transmissions for twenty-five years.

Semi-Solid in a PHEV Changes the Calculus

PHEVs run smaller packs than BEVs, typically 15 to 25 kWh instead of 70 to 100, which makes semi-solid adoption cheaper and faster to scale than dropping the same chemistry into a long-range EV. Yield problems on a novel cell chemistry are proportional to how many cells you need per car. MG needs fewer cells per PHEV, so MG can move sooner.

The cold-weather math is also friendlier here. A PHEV's electric-only window is 60 to 100 kilometres on a good day; a chemistry that holds power delivery in a Canadian February protects the part of the drive most owners actually use in electric mode. On a 500 km BEV, the same improvement is a buffer on a buffer.

For contrast, Samsung SDI targets pilot production of solid-state cells in 2027 for vehicles priced above $80,000 CAD. MG is landing a related-but-not-identical chemistry in the same year, in a segment where the outgoing ZS PHEV sits well under half that price in the UK. The premium tier and the family tier are converging on the same launch window from opposite directions.

Canadian relevance is more constrained. MG does not sell in Canada, and even if SAIC changed that tomorrow, its China-built PHEVs would sit outside EVAP on country-of-origin grounds and face the 100-percent-above-quota tariff regime that governs Chinese EVs post-January 2026. The 49,000-unit tariff-relief quota Canada opened in January 2026 applies to BEVs, not PHEVs. Canadian buyers do not get to price this one in yet.

The 2027 Number to Watch Is the ZS Sticker

Three PHEV models in 2027 plus the already-confirmed MG4 semi-solid BEV for Europe is four vehicles carrying the chemistry, a production commitment, not a concept-car reveal. Launching in PHEVs first is tactically the smarter path. Smaller packs mean lower exposure to per-cell yield risk on a chemistry that has not yet hit meaningful passenger-car volume anywhere.

The number to check when the next ZS lands is the delta against the outgoing model. If SolidCore adds less than about £1,500 to the sticker, the "battery chemistry is a premium feature" framing collapses the way it did for LFP once BYD proved the cost curve. If it adds £4,000, the technology is still parked in the halo tier and MG has simply moved the halo down one segment.

Either way, the floor for the plug-in hybrid segment moved at London Tech Day. The 2027 spec sheet everyone else is writing just got harder to defend.