SES Power recently searched the web for information on solid-state batteries, and we found some information from a Mercedes-Benz team leader (Hansen Chang) about what Mercedes-Benz is doing at the research level for solid-state batteries.

In fact, this information can be analyzed together with the information of another German luxury car company, BMW, whose common feature is that both of them are laying out the next generation of research (RD In-house):

● Mercedes-Benz

Mercedes-Benz is exploring the construction of a super battery plant in Europe with Stellantis, and will subsequently invest in ACC, a subsidiary of Stellantis.

Mercedes-Benz has invested mainly in Pfizer and Factorial Energy in the field of solid-state lithium batteries, and now through these two partnerships, intends to jointly develop next-generation solid-state batteries. At the same time, Mercedes-Benz has also increased its investment in battery anode materials, striving to do high energy density and improve fast charging speed.

● BMW

BMW's strategy is clear: it is starting to shift to cylindrical lithium battery attempts and is the only European car company that has not built a battery factory (but has built a very large scale battery pilot line).

In the field of solid-state lithium batteries, BMW plans to invest in SolidPower and deepen cooperation with it, and plan to install and test vehicles in 2022, launch solid-state lithium battery prototypes before 2025, and use them in production vehicles before 2030.

(Battery layout of two German luxury car companies)

A: Mercedes-Benz's judgment on the battery industry

According to the evolution of the power battery route for electric vehicles, in terms of energy density, the level in 2022 is about 500-700Wh/L, and the energy density of the cutting-edge high energy density battery is 700Wh/L.

Mercedes-Benz started from the traditional standardized (Lib standard) power battery, and will slowly cut into the frontier battery (Post LiB), and by 2030 can hit the 1,000Wh/L level to achieve a higher energy density battery.

This data is in accordance with 25 degrees, 1/3C test conditions to obtain the volume energy density Vol Energy Density.

(The evolutionary trend of battery energy density as judged by Mercedes-Benz)

In the future, Mercedes-Benz will develop solid electrolyte materials that are safer and have higher energy density than traditional lithium battery technology. In place of highly flammable organic electrolytes, safety and stability will be improved, which will make possible the real application of high-energy density materials.

Compared to current lithium batteries, solid-state batteries with sulfide electrolytes are superior in safety and other aspects, and polymer batteries are suitable for power type batteries (for high magnification). The advantages of oxide electrolyte batteries are high safety at high temperatures and high energy density. Solid-state lithium batteries with sulfide electrolytes are expected to be used in automotive applications, but there are still some problems to be solved.

As of now, Mercedes-Benz's solid-state battery technology is still only in the laboratory lab stage.

(Routes for different solid-state electrolytes)

In Mercedes-Benz's view, solid-state batteries have the following strategic values.

● Increase energy density and improve safety

● Differentiation of different vehicles (high-end models)

● In-house R&D (In house ASSB R&D) to develop materials and battery prototypes

(Mercedes-Benz's solid-state lithium battery DNA)

B: Prospects for solid-state batteries

At present, the development of solid-state batteries for many years, although many companies announced to invest a lot of money, but still in the initial stage, with the solid-state lithium battery startups in Europe and the United States listed, in this past 1 year, are not reached a state that can reach the installed car for real testing, so currently these startups and car companies are planning to commercialize the battery by 2025 (the initial car).

From the perspective of the cooperative car companies, even if the commercial readiness of solid-state batteries will start in 2025 (this point in time, car companies may buy a relatively high battery price), it is expected that the period of 2025-2030 for some luxury car companies to focus on the observation that they need to make the volumetric energy density of the battery high and make the battery light. This will help them to make the whole vehicle's overall mass low and improve the handling of the whole vehicle.

At present, we see that Chinese lithium battery companies need to rapidly increase the capacity of their mature products because the scale of traditional batteries is already very large, while taking into account the production testing and iteration of solid-state batteries in small batches to rapidly improve the technology level. We expect to see an explosion in this area of semi-solid-state batteries first, as many lithium battery companies are starting to plan their production capacity from 2GWh or even 5GWh in this area.

C: There are still many question marks

Battery cost has become a topic of great concern, and people are more willing to look forward to the low-cost performance of sodium batteries. The concept of solid-state lithium batteries has been hyped for so long that people have started to have doubts. Focus on semi-solid-state lithium batteries (condensed) may explode first, because its cost performance is a bit more appropriate.

As a manufacturer with nearly two decades of experience in the lithium battery industry, SES Power is very concerned about the safety of lithium battery systems while achieving the best price/performance ratio. For example, we use square aluminum-cased lithium iron phosphate batteries with good safety performance to make our products, such as lead-acid alternatives (12V100Ah, 12V200Ah, 24V100Ah, etc.). High current (2000A) starter lithium battery, UPS high voltage lithium battery system (up to 860V), 3Kw~20Kw off-grid, grid-connected, islanded lithium battery energy storage system, wall-mounted form of home energy storage system 48V100Ah, 48V200Ah, stacked energy storage system (single unit of 51.2V100Ah, supporting up to 15 stacks), etc.

If you have any questions about lithium batteries, you are welcome to contact us.