Yiwei EV: First Mass-Produced Electric Car with Sodium-Ion Batteries

Yiwei, JAC’s (Jianghuai Automobile Group) new all-electric Chinese car brand, has begun mass production of the first electric car fitted with sodium-ion batteries.

The final name of this compact city car has not yet been confirmed. For now, it is simply known as the Yiwei EV, with the first deliveries in China due to begin later this January.

Yiwei EV sodium-ion battery and construction

Using cylindrical sodium-ion cells supplied by another Chinese company, HiNa Battery, the Yiwei EV features JAC’s UE (Unitized Encapsulation) module technology, based on a honeycomb design (see image above).

Sodium-ion technology began with Sehol

Although Yiwei is the first manufacturer to mass-produce an electric vehicle using this battery technology, the story began with another Chinese brand: Sehol.

Until 2021, Sehol belonged to Volkswagen Anhui (see box), before joining JAC’s portfolio of brands. In 2023, it was announced that the Sehol brand would be phased out, with every one of its models renamed and incorporated into either JAC Motors or Yiwei.

The small electric vehicle featured here is one such example. Almost a year ago, it was unveiled as a prototype under the Sehol brand, carrying the E10X name. It remains unclear whether it will retain that designation when it reaches the market as a Yiwei, or whether it will receive a new one.

What is confirmed for now is that this small EV has a battery with a capacity of just 25 kWh, which can be charged from 10% to 80% in only 20 minutes.

Range and charging of the Yiwei EV

Its range is rated at 252 kilometres under China’s CLTC range cycle, which is considerably more generous than the European WLTP cycle.

As a rule, the CLTC cycle can produce figures up to 20% higher than WLTP, meaning this electric car’s range under European homologation should be around 200 km.

What is the main difference from a “conventional” battery?

Beyond the raw materials used, the key difference compared with the lithium-ion batteries found in most electric cars - NMC and LFP - is cost, which naturally has a significant effect on the vehicle’s final price.

Because they do not use metals such as lithium or nickel, sodium-ion batteries “are a low-cost solution that promotes the popularisation of electric vehicles for the masses”, as Yiwei president Xia Shunli explained in comments to Car News China.

However, this technology has increasingly been used for stationary energy-storage applications - in homes, for instance - largely because its energy density is lower than that of LFP (lithium iron phosphate) and NMC (nickel, manganese and cobalt) batteries.

To put this into perspective, the sodium-ion battery in this Yiwei has an energy density of 120 Wh/kg. An LFP battery, by comparison, can reach 160 Wh/kg, while an NMC battery can achieve 270 Wh/kg. This is therefore the principal limitation of sodium-ion batteries.

In other words, a sodium-ion battery requires more material than a lithium-ion battery of equivalent capacity, making it larger and heavier.

Source: Car News China