MG has beaten Toyota and Nissan to mass-produced semi-solid-state batteries. UK MG4 buyers are first in line.
Every EV charges more slowly in cold weather. That is a property of lithium-ion chemistry. The liquid electrolyte that allows lithium ions to move between the battery's positive and negative electrodes thickens and slows at low temperatures, which limits how quickly charge can flow into the cells. A battery that accepts 150kW in July will accept meaningfully less in January, and anyone who has sat at a public charger in December watching the speed indicator drop will already know this in their bones.
MG's SolidCore battery replaces 95% of that liquid electrolyte with solid material. The result, according to MG, is a battery that charges 15% faster in cold conditions and delivers 20% better power when you need it quickly, with the first production cars arriving in the UK before the end of 2026.
What semi-solid-state actually means
The battery world has three points on a spectrum. At one end is conventional lithium-ion, which has served the EV market well for fifteen years and uses a liquid electrolyte throughout the cell. At the other end is full solid-state, where the liquid is replaced entirely with a ceramic or polymer conductor. Full solid-state has been the industry's long-term goal for a decade. It promises higher energy density, better safety, faster charging, and longer life. In 2026, it is still not available in any production passenger car.
Semi-solid-state sits in the middle. By replacing most of the liquid electrolyte (in SolidCore's case, 95%), the battery gains most of the cold-weather and safety benefits of full solid-state while remaining manufacturable at scale. The liquid fraction that remains helps with the electrochemical interface, avoiding the brittle crack-formation issues that have slowed full solid-state development. It is an engineering compromise, and it is one that exists in a production car arriving at UK retail locations later this year.
Toyota has been working on solid-state battery technology since at least 2021 and is targeting production for 2028 at the earliest. Nissan has set the same target. QuantumScape, the US solid-state specialist backed by Volkswagen, is still in pre-production trials. MG announced mass production in March 2026, alongside the opening of its European Engineering Centre, and named the UK as the first market to receive SolidCore models.
What SolidCore claims, and what that means for UK use
When people say they worry about EVs in winter, the concern is almost always described as range anxiety. The more specific version is charging anxiety: the fear of arriving at a motorway charger with 15% battery remaining and watching it tick up at half the expected rate while the queue behind you grows. SolidCore addresses this directly.
Fifteen percent faster charging in low temperatures is the claim that matters most for UK use. Cold-weather charging slowdown is a real phenomenon, and the UK's latitude means meaningful portions of the year (November through March, at minimum) fall into temperatures where conventional lithium-ion batteries charge below their rated speed. A 15% improvement at 0°C or below is not a marginal gain. On a real-world motorway charger session on a winter morning, the difference between 150kW and 130kW effective charge rate is roughly seven minutes on a 10-80% top-up. That is the difference between one coffee and two.
The 20% improvement in power delivery transient response means the battery can release energy faster at the moment of hard acceleration, relevant in cold conditions where conventional batteries can feel sluggish off the line before they warm up. The commuter who pulls onto a dual carriageway at 7am in February will feel this before they have time to think about it.
Beyond cold-weather performance, MG cites improved safety: reducing the liquid electrolyte fraction lowers the risk of thermal runaway, the cascade failure mode responsible for the most serious EV battery incidents. Less flammable material in the cell is a straightforward safety improvement.
Which car gets SolidCore, and when
The first UK application is the MG4 Urban, already on sale from £23,495 in its current lithium-iron-phosphate form. MG has confirmed that SolidCore variants of the MG4 Urban will arrive in the UK before the end of 2026. Pricing for the SolidCore version has not been announced. MG's recent pricing history suggests the premium will be calibrated to stay competitive against the Tesla Model 3 and Hyundai Ioniq 6 rather than to maximise margin on the technology itself.
MG's 2026 product push extends well beyond SolidCore. The MGS6, MGS9 PHEV, MG2, and Hybrid+ models are all in the launch pipeline for the same year. SolidCore is part of an accelerating product programme, arriving at a point where MG already has 153 UK retail locations and a service infrastructure that most newer Chinese brands cannot yet match.
What SolidCore means for residuals and lease pricing
The MG4 Urban has shown stronger residual value retention than several other Chinese EVs at the same price point, a pattern reflected in funder appetite when quoting these cars. Part of that comes from MG's established brand recognition in the UK. Part comes from funders being able to see 153 retail locations and an established service network behind the quote.
SolidCore adds another data point in the same direction. Funders price residuals partly on technology risk: a battery that degrades faster, charges more slowly over time, or becomes a liability on a three-year-old used car reduces what a lease company can recover at disposal. A battery chemistry that holds its cold-weather performance better than conventional lithium-ion is directly relevant to that calculation. The effect on lease pricing will not be immediate, but as real-world UK performance data builds through 2027 and 2028, the cars with demonstrably better battery longevity will carry better residual support. That feeds into monthly payments.
What needs to be proved
MG's "world's first" claim on mass-produced semi-solid-state batteries will be scrutinised. Third-party testing of cold-weather charging performance on real-world UK public chargers, across the range of networks and ambient temperatures that UK drivers actually encounter, is the verification step that will confirm or qualify the published numbers. The 15% improvement is plausible given the chemistry. Whether it holds consistently at Gridserve or Osprey on a January morning is something UK owners will establish in the months after launch.
The secondary question for anyone considering the standard MG4 Urban now is whether to wait. That depends on how much the cold-weather performance concerns them and how soon SolidCore pricing is confirmed. The standard MG4 Urban is already one of the best-value EVs available in the UK at any price. The SolidCore version will be a more capable car in the conditions that matter most on this island.
The one figure MG has not yet confirmed for SolidCore is the revised WLTP range. Higher energy density typically means longer range in a given battery footprint, or the same range in a lighter, smaller pack. Until that number is confirmed, the range advantage of SolidCore over the current MG4 Urban's specification remains an estimate rather than a verified claim.
The manufacturers still developing solid-state batteries on slide decks are watching a production car leave a factory with 95% solid electrolyte before their first prototype reaches a public road. That is the technology gap MG is staking a claim on. UK buyers will find out this year whether the claim holds up in the conditions that matter.
The UK launch of the MG4 Urban is expected later this year. Be the first to hear about our lease offers on this car by subscribing to our lease deals newsletter.
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