MG4 with semi-solid-state battery shown at Guangzhou Motor Show

MG news is not exactly fresh, but the brand grabbed attention again at the Guangzhou Motor Show, where it unveiled for the first time an almost-production version of what will become its first mass-produced car fitted with a semi-solid-state battery pack.

We first saw the styling of the MG4 successor during the summer - the first generation has enjoyed notable success in Europe - yet one of the biggest developments is hidden from view.

MG returns to Guangzhou with the MG4 Anxin Edition

At the Guangzhou Motor Show in China (held this past weekend), MG presented the new variant it calls the MG4 Anxin Edition. This is not the first SAIC-owned model to debut the technology - that honour went to the IM 6 saloon - but it still matters: the MG4 is set to become one of the earliest high-volume models to adopt this new type of battery.

The MG4 range in China: LFP options

In China, the new MG4 already comes with two LFP (lithium iron phosphate) battery options (sales began in the summer): 42,8 kWh and 53,9 kWh. These deliver ranges of up to 437 km and 530 km respectively on the CLTC cycle.

Semi-solid-state battery: capacity, weight and motor

The semi-solid-state battery used in this MG4 keeps the same capacity as the LFP unit, at 53,95 kWh. For now, MG has not released consumption or range figures.

What is confirmed is the weight: this version is 15 kg heavier overall, bringing kerb weight to exactly 1500 kg. MG also states that it will use the same electric motor as other variants, producing 120 kW (163 cv) and 250 Nm.

Advantages of a semi-solid-state battery

The key distinction between today’s electric-car batteries and semi-solid-state batteries lies in the electrolyte. In traditional lithium-ion batteries, the electrolyte is liquid. In solid-state batteries, it is entirely solid. Semi-solid solutions sit between the two: the electrolyte consists of solid particles suspended in a conductive liquid.

The benefits start with safety, something SAIC says it has demonstrated through testing, including a puncture test carried out in three directions. Compared with lithium-ion chemistries (LFP and NMC), it also performs better in low temperatures: in sub-zero conditions, it can retain up to 75% of its range with pre-conditioning.

As well as improved safety, semi-solid batteries have the potential to provide higher energy density and are cheaper to manufacture than fully solid-state batteries. Their production process is also closer to that used for conventional lithium-ion packs - a key factor in the final price of electric cars.

When will it arrive?

MG has not yet announced a launch date for the MG4 with semi-solid-state batteries. The company has only said the new variant will be added to the line-up once production begins.

It is expected to be the most expensive version in the range, which in China is priced between 68 800 yuan (around 8390 euros) and 102 800 yuan (around 12 535 euros).

There is still no confirmation of when the second-generation MG4 will reach Europe - it went on sale in China at the end of the summer - and even less clarity on whether the semi-solid-state battery variant will be sold here.