Cheaper batteries for EVs are getting closer. Will LG Energy Solution solve the LMR problem?

In short:

Lithium manganese batteries (LMR) are considered one of the most promising technologies

The issues lie in their durability and gas generation inside the cells

It is possible that these obstacles will be overcome soon, according to recent research by LG Solution and scientists from Seoul National University

The developed cells retained 92.2% of their initial energy after 883 full charge and discharge cycles

LG and cheaper batteries on the horizon

The race for cheaper and more efficient batteries for electric vehicles is in full swing. One area that has attracted significant interest from the industry over the past few years are batteries using lithium manganese-rich (LMR) cathodes.

Scientists from LG Energy Solution, together with a team led by Prof. Jongwoo Lim at Seoul National University, have reported progress in solving one of the most significant challenges facing this technology. The research findings were published in the journal “Nature Communications” and indicate that proper management of charging, discharging, and cell formation processes can significantly improve the stability of large LMR cells used in electric vehicles.

LMR technology is attractive primarily because it allows the use of manganese, which is a much cheaper raw material than cobalt. At the same time, it retains the potential for high energy density thanks to electrochemical reactions that occur not only involving nickel and manganese but also oxygen present in the cathode structure — according to the Electric CarS Report.

Oxygen was the biggest problem.

It is precisely the activity of oxygen that has so far been the main obstacle to the commercialization of LMR batteries. During charging, some oxygen in the cathode structure gets oxidized. If it does not return to its original state during discharging, it can lead to degradation of the cathode material and gas formation inside the cell.

In the case of large cells used in electric vehicles, this problem is particularly significant. The limited amount of free space inside the cell means that gases that accumulate can increase pressure, degrade battery performance, shorten its lifespan, and also affect safety — writes Herald Corp.

Researchers analyzed oxygen behavior under various charging and discharging conditions. It turned out that not only the maximum charging voltage but also the lower limit of the discharge voltage is crucial.

During tests, reducing the upper charging voltage from 4.6 V to 4.3 V increased the efficiency of restoring oxidized oxygen from 86% to 97%. Additionally, lowering the final discharging voltage from the typical 3.0 V to 2.0 V allowed oxygen to be restored to nearly its original chemical state, according to Yahoo Finance.

Almost 900 cycles and over 92% capacity

Based on these results, LG Energy Solution redesigned the operating voltage range and the manufacturing process for large LMR cells with a capacity of 40 Ah. The company also used lower-temperature processing, which helped reduce gas generation.

The results were promising. The developed cells retained 92.2 percent of their initial energy after 883 full charge-discharge cycles. This is one of the most significant findings of the study, as durability and gas generation had previously been the main barriers to using LMR technology in large traction batteries.

As Prof. Jongwoo Lim emphasized, “The study helped identify the causes of LMR battery degradation from the perspective of oxygen reaction reversibility and showed that cell stability can only be improved through proper design of electrochemical protocols,” according to the Korea Herald.

On the other hand, representatives from LG Energy Solution stated that the results demonstrate the possibility of effectively reducing gas generation while maintaining stable cycle life, which could accelerate the commercialization of this technology.

Another step toward cheaper electric cars

If laboratory results can be translated into mass production, LMR batteries could become a significant alternative to the currently used cells based on expensive materials, especially cobalt. For car manufacturers, this would mean the possibility of reducing battery costs without sacrificing high energy density.

Of course, the path to full commercialization is long, but recent research shows that the future of batteries doesn’t have to rely solely on new materials. Sometimes, a better understanding and control of the processes occurring within the cell prove equally important — analyzes The Korea Times.

Which battery technologies are used on a large scale today?

Currently, lithium-ion batteries dominate electric vehicles almost entirely, but they come in several main chemical variants:

• NMC (nickel-manganese-cobalt)

The most popular technology in many European, Korean, and Japanese vehicles. It combines high energy density with good range.

• NCA (nickel-cobalt-aluminum)

A technology with very high energy density, used by Tesla in some of its models produced in the US and by certain premium manufacturers.

• LFP (lithium-iron-phosphate)

The fastest-growing segment of the market currently. These batteries are cheaper, do not use cobalt or nickel, and feature high durability and safety.

LMFP (lithium-manganese-iron-phosphate)

A developed version of LFP with manganese added to increase energy density while maintaining low costs. The first commercial applications are already emerging, mainly in China.

• LTO (lithium-titanate)

A niche technology primarily used in buses, energy storage systems, and specialized vehicles. It offers very fast charging and exceptional durability, but has low energy density.

• LMR (lithium manganese-rich)

This is the latest technology that LG Energy Solution is working on. It is not yet produced in large quantities, but it is seen as a candidate for the next generation of traction batteries due to its ability to reduce costs and decrease reliance on cobalt.

Oskar Włostowski