Battery Storage State Estimation (SOC/SOH) Patent Landscape
The battery SOC/SOH state estimation field is highly concentrated, with LG Energy Solution holding a commanding lead and the top five filers together accounting for 46% of the hundred largest filers’ combined output. The field reached peak annual volume around 2021 and has since plateaued, though multi-year growth remains positive at 24% over the recent window.
LG Energy Solution leads a concentrated field with a clear tier gap
LG Energy Solution holds the top position with 467 patent families, nearly one-third more than second-ranked Samsung SDI at 353 patent families. Robert Bosch, Contemporary Amperex Technology (Hong Kong), and Contemporary Amperex Technology Co. complete the top five, establishing a dominant Korean–German–Chinese triad at the apex of this field.
The top five filers collectively account for 46% of the combined output of the hundred largest filers, signaling a high-concentration landscape where a small cohort of battery manufacturers and automotive suppliers controls the majority of IP. A notable tier gap separates the top two from the remainder: LG Chem and Denso both register 56 patent families, roughly 12% of LG Energy Solution’s count.
| # | Applicant | Patent families | Share |
|---|---|---|---|
| 1 | LG Energy Solution Ltd. | 467 | |
| 2 | Samsung SDI Co., Ltd. | 353 | |
| 3 | Robert Bosch GmbH | 148 | |
| 4 | Contemporary Amperex Technology (Hong Kong) Limited | 140 | |
| 5 | Contemporary Amperex Technology Co., Ltd. | 111 | |
| 6 | LG Chem Ltd. | 56 | |
| 7 | Denso Corporation | 56 | |
| 8 | Toyota Motor Corporation | 48 | |
| 9 | Huawei Digital Power Technologies Co., Ltd. | 48 | |
| 10 | Hyundai Motor Company | 37 |
| # | Applicant | Patent families | Share |
|---|---|---|---|
| 11 | CPS Technology Holdings LLC | 36 | |
| 12 | SK On Co., Ltd. | 33 | |
| 13 | Samsung Electronics Co., Ltd. | 31 | |
| 14 | Lnventus Power Inc. | 30 | |
| 15 | ABB (Switzerland) AG | 27 | |
| 16 | SZ DJI Technology Co., Ltd. | 27 | |
| 17 | State Grid Corporation of China | 26 | |
| 18 | Matter Motor Works Pte. Ltd. | 25 | |
| 19 | ZOLL Circulation Inc. | 24 | |
| 20 | Hyperdrive Innovation Ltd. | 22 |
The leaders’ positions reflect vertically integrated strategies — the top applicants are primarily battery cell makers and automotive system suppliers, meaning their SOC/SOH IP is tightly coupled with their product roadmaps. New entrants seeking freedom to operate will likely encounter dense prior art in the core estimation and battery management spaces.
Filing counts for 2025 and especially 2026 are understated due to publication lag and should not be interpreted as a decline in activity. Longer-window growth, applicant concentration, and technology-route coverage are therefore more reliable signals than the latest-year bar alone.
Activity plateaued near its 2021 peak; power-supply and measurement classes dominate
Annual filing volume surged from 2017 through 2021, then stabilized at a high level, consistent with a maturing but still active field. The technology mix is anchored by power supply and grid systems, battery electrochemistry, and electric measurement — the three pillars of any BMS-integrated estimation system.
Annual filing trend
Filings grew rapidly from 182 in 2017 to a peak of 526 in both 2021 and 2022, then settled to 452–472 through 2023–2024. The 2025 and 2026 bars are materially undercounted due to patent publication lag and should not be read as a downturn.
↗ Hover for values · click a bar to ask EurekaTechnology composition
H02J (power supply and grid systems) is the dominant class, followed closely by H01M (batteries and fuel cells) and G01R (electric and magnetic measurement). The relatively small shares of G06F (digital data processing) and G06N (AI/computing models) indicate that algorithmic and machine-learning estimation approaches remain a secondary layer over a hardware-centric core.
↗ Hover for values · click a bar to ask EurekaHighly cited patent families surfaced by the query
Citation-heavy patent families returned by the query. Use this section as citation context, not as a curated list of the most topic-specific patents.
Battery Energy Storage System Management Apparatus…
In a BESS management apparatus, a history database stores operation history data related to operation history of a BESS and price history data related to price history of a service. A state estimation unit estimates a state of charge and a state of health of a battery. A simulation unit calculates a performance score of the BESS with respect to providing of… (excerpt from the patent abstract)
| # | Patent | Citations |
|---|---|---|
| 1 | System and method for tracking and archiving batte… | 832 |
| 2 | Battery management system for control of lithium p… | 824 |
| 3 | Battery management system and battery simulator | 389 |
| 4 | Battery management system | 278 |
| 5 | Battery management system | 254 |
| 6 | Battery management system and method | 216 |
| 7 | Systems and methods for battery management | 190 |
| 8 | Battery management system and driving method thereof | 175 |
Ranked by total forward citations. Citation counts favour older and broadly cited patent families, and broad or adjacent patents may appear when they match the search scope. Treat this section as citation context, not as a curated list of the most topic-specific patents. Some patent titles may be shown in their original, non-English language where an accurate translation could not be guaranteed.
What the competitive structure means for R&D strategy
Three structural signals stand out: the field is entering maturity, concentration is high but not absolute, collaboration is driven by strategic OEM–supplier pairs, and geographic coverage is anchored in the US and. China.
Field is at plateau — incremental innovation dominates core estimation
Annual filings have plateaued near their 2021 peak, placing this field squarely in the Maturity stage. The multi-year growth window still shows a 24% increase, but the era of rapid claim-staking in mainstream SOC/SOH estimation is largely over. R&D investment is better focused on adjacent algorithmic layers (AI models, digital processing) or specialized application domains rather than re-litigating the core BMS estimation space.
Maturity stageHigh concentration with a clear top-two; mid-tier is accessible
The top five filers hold 46% of the hundred largest filers’ combined total, and LG Energy Solution’s 467 patent families are 32% ahead of second-place Samsung SDI. However, the mid-tier — Robert Bosch at 148 patent families, CATL entities at 111–140 — shows that automotive Tier 1 and energy storage specialists can build meaningful positions. Companies outside the current top 20 have room to differentiate through application-specific or algorithmic approaches.
High concentrationSamsung SDI–Bosch is the dominant co-filing pair; OEM alliances follow
The most active co-filing pair is Samsung SDI and Robert Bosch, with 40 joint patent families — reflecting a long-standing battery–automotive supplier relationship. Hyundai Motor and Kia jointly filed on 16 families, while LG Chem and Silicon Works (a semiconductor affiliate) produced 9 joint families. CATL co-filed 6 families with its own software subsidiary, and Samsung SDI separately collaborated with Seoul National University (SNU R&D Foundation) on 1 family, indicating selective academic engagement.
Strategic alliancesUS leads in patent records; China and EPO are essential second filings
The United States accounts for the largest single-jurisdiction count, followed by China and Europe (EPO). WIPO PCT and India round out the top five filing destinations, with India’s presence reflecting growing EV market importance. South Korea and Japan also carry significant coverage given the national origins of the leading applicants. A full global freedom-to-operate analysis must span at minimum the US, China, and EPO jurisdictions.
US · China · EPOGo beyond the landscape: Eureka’s TRIZ Solution agent breaks down an R&D problem and returns patented concept solutions, each with a technical approach and cited patent & literature evidence.
| Applicant | Collaborator | Co-filings |
|---|---|---|
| Samsung SDI Co., Ltd. | Robert Bosch GmbH | 40 |
| Hyundai Motor Company | Kia Corporation | 16 |
| LG Chem Ltd. | Silicon Works Co., Ltd. | 9 |
| Contemporary Amperex Technology Co., Ltd. (CATL) | Contemporary Amperex Runzhi Software Technology Co., Ltd. | 6 |
| Samsung SDI Co., Ltd. | Regents of the University of Michigan | 4 |
| Robert Bosch GmbH | Bosch AG | 2 |
| Toyota Motor Corporation | Toyota Central R&D Labs, Inc. | 2 |
| LG Energy Solution Ltd. | Regents of the University of Michigan | 1 |
| Samsung SDI Co., Ltd. | Seoul National University R&DB Foundation | 1 |
| Contemporary Amperex Technology Co., Ltd. (CATL) | Contemporary Amperex Technology (Shanghai) Intelligent Technology Co., Ltd. | 1 |
Co-filing pairs, ranked by the number of jointly-filed patent families.
LG Energy Solution accelerates while Samsung SDI grows steadily; CATL pulls back
The top two players are both increasing recent filing rates, but their technology emphases differ in emphasis between measurement-first and power-management-first approaches. CATL’s retreat in recent filings opens relative space in the mid-field.
LG Energy Solution
LG Energy Solution leads the field with 467 patent families and is accelerating, with recent-period filings up 112% versus the prior three-year window. Its technology emphasis centers on G01R 31 (electric measurement, 253 records), H02J 7 (power supply and charging, 218 records), and H01M 10 (battery cells, 167 records) — a measurement-first profile that reflects deep integration of state estimation into cell-level design. This trajectory suggests continued aggressive IP build-out.
patent families: 467Samsung SDI
Samsung SDI holds second place with 353 patent families and shows steady momentum, with recent filings up 17% versus the prior period. Its portfolio is weighted toward H02J 7 (power supply and grid systems, 297 records) ahead of H01M 10 and G01R 31 — a power-management-first profile distinguishing it from LG Energy Solution’s measurement emphasis. Samsung SDI is also the most active co-filer in the field, partnering with Robert Bosch on 40 joint families and with the University of Michigan on 4 families.
patent families: 353| Applicant | Recent (3 yrs) | Trend |
|---|---|---|
| LG Energy Solution Ltd. | 218 | ▲ +112% |
| Samsung SDI Co., Ltd. | 21 | ▲ +17% |
| Contemporary Amperex Technology Co., Ltd. (CATL) | 60 | ▼ -66% |
| Robert Bosch GmbH | 10 | ▼ -29% |
| Denso Corporation | 35 | ▲ +106% |
| Toyota Motor Corporation | 30 | ▲ +114% |
| Huawei Digital Power Technologies Co., Ltd. | 30 | ▲ 3.0× vs prior 3-yr |
| Hyundai Motor Company | 2 | ▲ new entrant |
AI models and protective circuit arrangements are under-served adjacent branches
Against a corpus dominated by power-supply and measurement classes, several branches carry plausible technical relevance to SOC/SOH estimation but remain sparsely covered. These are observations of relative sparsity — not validated opportunities — but two branches have sufficient technical rationale to warrant closer examination.
G06N · Computing based on AI models
This branch holds a 2% share of patent records, despite machine-learning-based state estimation (neural networks, Kalman filter hybrids, physics-informed models) being an active area of academic and industry research. The sparse coverage relative to the dominant hardware classes suggests that algorithmic estimation IP has not yet been filed at scale under G06N. For teams with deep ML expertise, this branch represents an under-served adjacent space where differentiated filing may be achievable without confronting the densest prior art in H02J or G01R. Entry is feasible for any organization with battery-specific training datasets and embedded inference capability.
Search this in Eureka →H02H · Protective circuit arrangements
H02H holds a 1% share of patent records, reflecting limited explicit intersection between state estimation and protection circuit design. Yet accurate SOC/SOH signals are a prerequisite for over-charge, over-discharge, and thermal runaway prevention — making this an area where estimation and protection IP naturally converge. The sparsity may reflect classification practice rather than a true gap, but organizations developing integrated BMS-protection architectures may find less crowded claim territory here than in the core estimation classes.
Search this in Eureka →How leading filers differ across core technology routes
Route coverage across the main technology branches in the current evidence set.
| Player | H02J 7 · Power supply & grid systems | G01R 31 · Electric & magnetic measurement | H01M 10 · Batteries, cells & fuel cells | B60L 58 · Electric vehicle propulsion | H02J 3 · Power supply & grid systems |
|---|---|---|---|---|---|
| LG Energy Solution Ltd. | Strong · 218 | Strong · 253 | Strong · 167 | Moderate · 101 | Absent |
| Samsung SDI Co., Ltd. | Strong · 297 | Moderate · 114 | Moderate · 122 | Emerging · 13 | Emerging · 7 |
| Contemporary Amperex Technology Co., Ltd. (CATL) | Strong · 176 | Strong · 105 | Strong · 101 | Moderate · 38 | Absent |
| LG Chem Ltd. | Strong · 146 | Strong · 79 | Strong · 111 | Emerging · 12 | Absent |
| Robert Bosch GmbH | Strong · 108 | Moderate · 51 | Strong · 61 | Absent | Absent |
| Denso Corporation | Strong · 50 | Strong · 47 | Strong · 41 | Moderate · 12 | Absent |
| Toyota Motor Corporation | Strong · 31 | Strong · 20 | Strong · 33 | Moderate · 9 | Moderate · 9 |
Frequently asked questions
The landscape contains 3,406 patent families in scope. Filing activity grew from 182 families in 2017 to a plateau of 526 in both 2021 and 2022, reflecting rapid expansion followed by stabilization in a maturing field.
LG Energy Solution leads with 467 patent families, followed by Samsung SDI with 353 and Robert Bosch with 148. Contemporary Amperex Technology (Hong Kong) and Contemporary Amperex Technology Co. rank fourth and fifth respectively.
The field shows a 24% increase over the recent multi-year window, but annual filings have plateaued near their 2021 peak rather than continuing to climb. This is consistent with a Maturity lifecycle stage where incremental and adjacent innovation takes precedence over foundational claim-staking.
The United States has the largest patent-record count, followed by China and Europe (EPO). WIPO PCT and India are the next most significant filing destinations. Any comprehensive freedom-to-operate assessment should cover at minimum the US, China, and EPO jurisdictions.
Samsung SDI and Robert Bosch are the most active co-filing pair with 40 joint patent families. Hyundai Motor and Kia follow with 16 joint families. LG Chem and Silicon Works produced 9 joint families, and CATL co-filed 6 families with its own software subsidiary.
The most technically relevant under-served branches relative to the dominant classes are G06N (AI and computing models, 2% share) and H02H (protective circuit arrangements, 1% share). Both are sparsely covered despite having clear technical adjacency to accurate SOC/SOH estimation in battery management systems.
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Disclaimer. This page is generated from PatSnap Eureka data drawn from a limited snapshot of global patent and scientific-literature records, and is provided for general information and reference only.
Patent data carries inherent limitations: recent filings (typically the most recent 18–24 months) are under-counted due to standard publication lag; counts may be reported at either a patent-family or a patent-record basis and are not always directly comparable; classification, applicant-name, and citation data may contain errors, duplicates, or omissions; and the underlying search query defines and constrains the scope shown. As a result, the analysis may be incomplete or inaccurate and may not reflect the full technology landscape.
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