[Patent Analysis] LG Energy Solution’s Bimodal LMR Cathode Patent (WO2026038783A1) — The Scope of a Three-Particle Combination That Prevents Rolling Fracture

What’s at Stake: An International Application That Shields LMR’s Weakness with a Particle Combination

LG Energy Solution’s international application WO2026038783A1 seeks to solve the problem of manganese-rich LMR cathode material fracturing during electrode rolling by mixing two types of LMR particles of different sizes with one type of single-particle NCM particle. The core of the scope of rights is not the general idea of “mixing particles of different sizes,” but the combination of three particle groups that must include a low-manganese third particle, together with the particle-size and composition figures for each particle.

To start with the industry backdrop, lithium manganese-rich (LMR) cathode material has been regarded as a next-generation cathode chemistry that lowers the nickel share and raises the manganese share, aiming to capture cost competitiveness and energy density at the same time. On May 13, 2025, GM and LG Energy Solution announced plans to apply prismatic LMR cells to GM’s next-generation electric trucks and full-size SUVs, with pre-production at an LG Energy Solution facility in late 2027 and commercial production starting in 2028 at the Ultium Cells joint venture in the United States. In the same announcement, GM stated that LMR cells have 33% higher energy density than the best-performing LFP cells.

The tension lies in the material itself. LMR material has carried a structural weakness: because of its low density and large BET specific surface area (particle surface area measured by gas adsorption), its particles break easily. When particles fracture during the electrode rolling process, electrode density drops and porosity increases, creating a vicious cycle that lowers the energy density of the whole cell. This piece lays out what the claim elements of this international application are meant to protect, and which design variables a competitor developing a similar material should be careful about.

Basic Mechanism: Gravel, Sand, and a Cushion

The core idea of this application is close to the principle that packing gravel together with sand leaves fewer gaps than packing large gravel alone. If an electrode is made from LMR cathode particles alone, the particle sizes are distributed similarly (a unimodal distribution), so stress concentrates on specific particles during rolling and they fracture easily. This application mixes large LMR particles (the first particles), small LMR particles (the second particles), and single-particle NCM particles containing nickel, cobalt, and manganese but with a lower manganese share than LMR (the third particles).

The design is such that the small particles fill the empty spaces between the large particles, dispersing the stress applied during rolling, so that high density and low porosity are achieved together without particle fracture. The specification explains that the resulting bimodal distribution (a particle-size distribution with two peaks) effectively buffers rolling stress. To extend the analogy, the third particle is “hard sand” that does not crumble easily. Unlike secondary particles made of many agglomerated primary particles, a single particle is one crystal lump, so it has fewer boundaries along which to split during rolling.

The reason NCM was chosen as the third particle is gas. The specification states that adding a nickel-cobalt-manganese third particle reduces gas generation during LMR’s activation step and during charge-discharge. In other words, a single design aims at three effects.

• Fracture suppression: the bimodal distribution buffers rolling stress
• Density improvement: higher electrode density achieved without fracture
• Gas reduction: the low-manganese NCM third particle reduces activation and charge-discharge gas

Comparison: Roles and Figures of the Three Particle Groups

The table below keeps the original comparison table but corrects the basis of the third-particle ratio after checking it against the claims on Google Patents.

Category	Constituent particles	Particle-size distribution	Main purpose	Note
Conventional single-type LMR cathode	LMR particles only, single type	Unimodal	High capacity, low cost	Vulnerable to particle fracture and gas generation during rolling
WO2026038783A1 (1st + 2nd particles)	Mix of large- and small-diameter LMR particles	Bimodal (primary)	Disperses rolling stress	D50 approx. 7-20 μm (large) / 1-6 μm (small)
WO2026038783A1 (adding 3rd particle)	+ single-particle NCM (Ni 50 mol% or more, Mn 40 mol% or less)	Bimodal (final)	Reduces gas generation + suppresses fracture	D50 2-5 μm; 5-95 wt% of the 2nd + 3rd particles combined (dependent claim)

What this table says: The first particles are set at D50 7-20 μm, the second at 1-6 μm, and the third at 2-5 μm, and the weight ratio of first particles to (second + third particles) is claimed at 50:50 to 95:5. The substance of the protected scope lies not in particle-size mixing itself but in the third component: single-particle NCM with 40 mol% manganese or less.

Laying out the bibliographic history in a table shows the timeline for securing rights. In particular, the “anticipated expiration” shown on Google Patents should be read as a deadline of the international phase, not as the end of the patent term.

Date	Event	Meaning
2024-08-13	Korean application KR10-2024-0108199	Earliest priority date
2025-08-04	Korean application KR10-2025-0106778	Second priority basis
2025-08-06	International application PCT/KR2025/011749	Filed within 12 months of the claimed priority
2026-02-19	International publication WO2026038783A1	18 months from the earliest priority date
2027-02-13	“Anticipated expiration” shown on Google Patents	30 months from the earliest priority date; matches the usual national-phase entry deadline

What this table says: February 13, 2027 falls exactly 30 months after the earliest priority date (2024-08-13), and this date should not be read as the lapse of rights. The actual fate of the rights depends on which countries the application enters in the national phase by then.

Patent Perspective: Gist of the Claims and Design-Around Points

WO2026038783A1 (title: Positive electrode active material, and positive electrode and lithium secondary battery comprising same; applicant LG Energy Solution Ltd; inventors Bae Sang-ho, Heo Min-ji, Kim Yeo-jin) was filed as PCT/KR2025/011749 on August 6, 2025 and published on February 19, 2026. According to Google Patents, its status is Pending. According to GM’s 2025 announcement, LG Energy Solution holds more than 200 LMR-related patents across major patent offices and has researched LMR since 2010, so this application can be seen as adding a layer of “electrode-process compatibility” on top of an existing LMR portfolio.

Restated, the elements of claim 1 are as follows.

• (a) First and second particles: a manganese-rich lithium metal oxide with a layered crystal structure, a lithium molar ratio exceeding 1 relative to the non-lithium metals, and manganese at 50 mol% or more of the non-lithium metals. Formula 1 is Li_a[Mn_bNi_cM_d]_2-aO₂, where a>1, 0.5≤b<1, 0≤c≤0.5, 0≤d≤0.5, and c+d≤0.5.
• (b) Particle size: first particles D50 7-20 μm; second particles D50 1-6 μm.
• (c) Third particles: a lithium nickel-cobalt-manganese composite oxide in single-particle or quasi-single-particle form, with manganese at 40 mol% or less, nickel at 50 mol% or more, and D50 2-5 μm.
• (d) Weight ratio: first particles : (second + third particles) = 50:50 to 95:5.

The dependent claims add further limitations, such as a total BET specific surface area of 0.1-5.0 m²/g and the third particles making up 5-95 wt% of the second and third particles combined. The fact that these elements are claimed together as a combination is the crux of any design-around.

Design-around scenarios (including counterarguments) fall into three branches.

• Omitting the third particle: mixing LMR particles in only two sizes to create a bimodal distribution drops element (c), leaving room to avoid literal infringement. However, the gas-reduction effect emphasized in the specification becomes hard to obtain, creating a trade-off between avoidance and performance. In this respect, the claim appears to have been drafted quite deliberately.
• Composition-boundary avoidance: designing the third particle’s manganese content above 40 mol% may also fall outside element (c). This, however, blurs the chemical distinction from LMR and requires separate review.
• Particle-size-boundary avoidance: between the upper limit for the second particles (6 μm) and the lower limit for the first particles (7 μm) lies a range the claim does not define. D50 values can vary with the measurement method, however, so designs near the boundary values carry considerable potential for disputes over measurement conditions.

To add our own interpretation: this claim contains a “composition gap” of manganese above 40 mol% and below 50 mol%. It is a region that falls neither within the third-particle definition (manganese 40 mol% or less) nor within the first/second-particle definition (manganese 50 mol% or more with a lithium molar ratio above 1). A design that uses mid-manganese particles from this gap as the third component may lie outside the claim on its literal terms, but if it delivers the same function and effect of gas reduction, the likelihood of facing a doctrine-of-equivalents claim also rises. The gap may be both an opportunity for avoidance and a battleground for equivalents disputes.

Limits and Outlook: The Mass-Production Process Will Decide the Value of the Rights

Optimistically, if this application is applied on an actual mass-production line, LG Energy Solution could secure a double advantage: retaining LMR’s cost benefit while reusing existing NCM mass-production infrastructure (single-particle synthesis processes) to solve the electrode-density problem. The fact that its timing overlaps with the 2028 commercial-production plan adds to the business weight of this application.

There is a counter-scenario, however. The slurry process required to mix and disperse the three particle groups uniformly at a precise ratio could itself become a new yield variable at the mass-production stage, and a larger share of small-diameter particles could burden the electrode slurry’s viscosity and coating stability, a possibility that cannot be ruled out. Moreover, an international application is not itself a right, so the claims may be narrowed or registration refused in each country’s examination.

As a strategic alternative, if a competitor is considering a similar bimodal design, independent development that replaces the third particle with a different low-manganese lithium transition-metal oxide family (for example, LFP-coated particles) rather than NCM is judged to be a point that could pursue both claim avoidance and differentiation. Even then, FTO on patents covering LFP-type additives must be checked separately.

Practical action: IP and planning staff are advised to put February 13, 2027 (30 months from the earliest priority date) on the calendar and to create a monitoring item that checks, around that date, whether this international application enters the national phase in the US, China, Europe, and Korea, along with each country’s amended claims, on KIPRIS and Espacenet.

Items requiring verification

• Whether the “bimodal volume-cumulative particle-size distribution” is an explicit limitation of claim 1 or an explanation in the specification (check against the original claim text)
• Whether WO2026038783A1 has entered the national phase in each country, and the country-specific claim amendments
• Gas-generation and electrode-density figures in the specification’s examples and the margin of improvement over the comparative examples

Sources

1. Google Patents, WO2026038783A1 “Positive electrode active material, and positive electrode and lithium secondary battery comprising same” (LG Energy Solution Ltd), bibliographic data, claims, and specification
2. General Motors press release, “GM and LG Energy Solution to pioneer LMR battery cell technology,” 2025-05-13