COMPANY PROFILE / NEXT-GEN ENERGY STORAGE
NGK Insulators (now NGK Corporation)
The company that first commercialized the NAS (sodium-sulfur) battery, and decided in October 2025 to end its manufacture and sale
For long-duration storage, NGK Insulators is a name that cannot be left out. It commercialized the NAS battery, which uses sodium, sulfur and a solid ceramic electrolyte, in 2002, the first in the world. From 2019 it also worked with BASF of Germany, selling an improved model, "NAS MODEL L24", overseas. But on 31 October 2025 its board decided to end the manufacture and sale of NAS batteries and to take no new orders. The reasons the company gave are that talks with BASF on expanding supply capacity were halted in September 2025, that building continuing demand for long-duration, large-capacity storage is expected to take time, that component costs have surged, and that competition with lithium-ion batteries has intensified. The final shipment is planned for around January 2027, and the company says it will continue after-sales service for equipment already delivered. On 1 April 2026 the company changed its name from "Nippon Gaishi" (NGK Insulators, Ltd.) to "NGK Corporation". This profile covers NAS batteries (the energy storage business) only, not the company as a whole, and sets out from primary sources what the company committed, with whom it worked and why it decided to end the business.
- NGK in 30 seconds, and where it stands in next-generation energy storage
- The logo and how the name is written
- Where the company sits in the field
- Scale (kept brief, limited to NAS batteries)
- Resources committed to next-generation energy storage
- What it has done so far
- What comes next
- What the company is aiming for in energy storage
- Map of partnerships in next-generation energy storage
- Technologies, products and services
- The risks this company carries
- Glossary, references and claim-to-source audit
1. NGK in 30 seconds, and where it stands in next-generation energy storage
Nagoya Premier, code 5333As stated in the 31 October 2025 disclosure
chemistries (NAS battery)Sodium-sulfur battery. The business is now being wound up
(decided 31 Oct 2025)Final shipment planned for around January 2027. After-sales service continues
FY2025: ¥11.77 billionMainly NAS batteries. 1.04% of consolidated revenue in FY2024 (year to March 2025)
expense of ¥19.96 billionExtraordinary loss in the year to March 2026, of which ¥12.27 billion is a provision
The NAS battery took up early the central problem of next-generation energy storage, long-duration, large-capacity storage. The company describes it as "the world's first practical megawatt-class power storage system" Sourced. Yet the company stopped making and selling it, not because there is no demand, but because it judged that building continuing demand for long-duration, large-capacity storage still takes time, and that, with component costs rising and competition from lithium-ion batteries, stable operation and profit would be hard to secure in future. In April 2025 it had said the potential demand for long-duration energy storage (LDES) was large, and was in talks with BASF and other companies it hoped to bring in on expanding supply capacity and cutting costs; those talks were halted in September 2025. So this profile is not a story that "long-duration storage became unnecessary". It is better read as a case in which even a company that moved early could not keep the business going with this method.
2. The logo and how the name is written
A note on names: on 1 April 2026 the company changed its name from "Nippon Gaishi Kabushiki Kaisha" (registered as Nippon Gaishi; in English NGK INSULATORS, LTD.) to NGK Corporation. This profile is filed under NGK Insulators, but the current legal name is NGK Corporation. Documents the company issued in October 2025 use the old name, and the June 2026 Securities Report uses the new one. NAS® is a registered trademark of the company, not a legal entity. BASF Stationary Energy Storage GmbH is a subsidiary of BASF and the co-development partner. HH2E is a German green-hydrogen company and the customer that ordered NAS batteries through BASF (its restructuring is covered in chapter 6). This profile covers NAS batteries only; it does not cover automotive exhaust ceramics, semiconductor manufacturing equipment products, insulators and other businesses. The logo image was taken from NGK's official website.
Official site: https://www.ngk.co.jp/3. Where the company sits in the field
This series sorts companies in next-generation energy storage into four types: cells & materials, long-duration & new chemistries, storage systems & operators, and recycling. NGK's NAS battery uses a chemistry different from lithium-ion (sodium and sulfur), and the company presents "long-duration, large-capacity" as its feature, so it falls under long-duration & new chemistries. NGK made the cells itself (at the Komaki Plant in Aichi) and sold them as systems, covering both cells and storage systems, but in October 2025 it decided to end manufacture and sale.
4. Scale (kept brief, limited to NAS batteries)
NGK is a ceramics company making automotive exhaust-purification ceramics, semiconductor manufacturing equipment products, insulators and more. The NAS battery sits in "Energy Storage" within the "Energy & Industry" business. Only the group totals and the figures for this business are shown here Sourced.
| Indicator (¥ million) | Year to March 2025 | Year to March 2026 |
|---|---|---|
| Net sales (consolidated) | 619,513 | 670,125 |
| Operating profit (consolidated) | 81,241 | 94,997 |
| R&D expenses (whole group) | n/a | 31,786 |
| Capital expenditure (whole group, tangible and intangible) | 48,807 | 55,848 |
| Consolidated employees | 19,931 | 19,869 (of which Energy & Industry 1,307) |
The "Energy & Industry" business, and Energy Storage (NAS batteries)
| ¥ million | Year to March 2025 | Year to March 2026 |
|---|---|---|
| Energy & Industry net sales (to external customers) | 57,553 | 65,253 |
| Same business, segment result | -4,196 | -1,322 |
| of which Energy Storage (NAS battery) sales | 6,473 | 11,772 |
| of which insulator sales | 51,080 | 53,481 |
| Energy Storage as a share of consolidated sales | 1.04% | about 1.8% Our calculation |
The share for the year to March 2026 is 11,772 ÷ 670,125, about 1.76% (our calculation). The 1.04% for the year to March 2025 is the value the company gave in its 31 October 2025 disclosure. For the year to March 2027 (fiscal 2026), the company expects Energy & Industry sales of ¥65.0 billion and operating profit of ¥4.0 billion, and says that for Energy Storage it will continue only to handle orders already taken and after-sales service, with "negligible" effect on profit Not yet confirmed (segment definitions were partly changed in April 2026, and the figures are on the new basis).
The results of the Energy & Industry business include insulators and other power transmission products, so operating results for NAS batteries alone are not disclosed Not yet confirmed. The company's explanation is that in the year to March 2025 it reviewed its production set-up as overseas demand slowed, booked a write-down of inventory, and the NAS battery loss widened, and that in the year to March 2026 the loss was expected to continue because part of the process remained shut down. As for why sales rose in the year to March 2026, in April 2025 the company had said shipments were expected to increase, mainly of domestic projects. It then decided in October 2025 to end the business, and says it will ship and deliver orders already taken from the inventory it holds. We could not confirm the breakdown of actual shipments.
5. Resources committed to next-generation energy storage
Most headcount and money figures are not disclosed for NAS batteries alone. What we could confirm, and what we could not, is set out below.
| Type of resource | What primary sources confirm | Category |
|---|---|---|
| People | The Energy & Industry business has 1,307 employees (plus 343 temporary staff on annual average, end of March 2026), including insulators and other products. Headcount dedicated to NAS batteries is not disclosed. The company says employees engaged in NAS battery manufacture and sale are to be reassigned within the group | Sourced / not disclosed |
| Money (R&D) | R&D expenses of the Energy & Industry business were ¥724 million in the year to March 2026 (product development and performance improvement of insulators and distribution equipment, plus NAS battery R&D). The NAS share is not disclosed | Sourced / not disclosed |
| Money (capital expenditure) | Capital expenditure of the Energy & Industry business was ¥2,752 million in the year to March 2026, mainly insulator production equipment. Past capital expenditure on NAS batteries could not be found | Sourced / not found |
| Money (losses from ending the business) | In the year to March 2026 the company booked a business restructuring expense of ¥19,959 million as an extraordinary loss and set up a provision for business restructuring of ¥12,270 million. The provision mainly covers disposal of NAS battery inventory and the cost of services the company must provide. It had also booked a write-down of inventory in the year to March 2025 as overseas projects slowed (amount not found) | Sourced |
| Investment, M&A, joint ventures, divestment | It worked with BASF (Germany) from 2019, and with BASF subsidiary BASF Stationary Energy Storage GmbH co-developed and sold the improved "NAS MODEL L24". Talks on expanding supply capacity and cutting cost (with other companies invited to join) were halted in September 2025. No equity investment, acquisition, joint venture or sale of the business was found (the business is being ended, not transferred) | Sourced / not found |
| Public funding and research institutions | The company's product page says NAS batteries were developed jointly with Tokyo Electric Power Company (no date given). No government subsidy or university joint research is mentioned in the materials we reviewed | Sourced / not found |
Status of main products and facilities
| Product or facility | Location | Scale | Stage | Dates and notes |
|---|---|---|---|---|
| NAS battery production facilities (Komaki Plant) | Komaki, Aichi | Production capacity not found | Partly halted in March 2025; end decided in October 2025 | The Securities Report lists production equipment for NAS batteries for power storage at the Komaki Plant. In March 2025, when the second lot of the HH2E project was cancelled, part of the plant was temporarily shut down. The final shipment is planned for around January 2027 |
| NAS standard system (container type) | n/a | Rated output 800 kW, rated capacity 4,800 kWh (manufacturer's stated value) | Sales ended | Battery and control equipment in a 20-foot (about 6 m) container. The company lists four containers of six 33 kW modules each |
| NAS standard system (package type) | n/a | Rated output 1,200 kW, rated capacity 8,640 kWh (manufacturer's stated value) | Sales ended | The package is assembled on site and holds module batteries. The company lists forty 30 kW modules |
| Improved "NAS MODEL L24" (co-developed with BASF) | Overseas | 36 containers in total shipped for the BASF project with HH2E (as of October 2024) | Sales ended | The company describes it as cutting investment by about 20% through less than 1% annual degradation and longer charge and discharge times (test conditions not given) |
| Overseas installation sites | Korea, Australia, Bulgaria, Maldives and others | Scale not found | In operation or ordered | Hydrogen production plant in Korea (operation began August 2020), renewable utilization in Korea (April 2023), renewable supply to an Australian mine (May 2023), seawater desalination in the Maldives (ordered July 2023), renewable utilization in Bulgaria (September 2023) |
6. What it has done so far
| When | What happened | Why it matters |
|---|---|---|
| 1962 | Komaki Plant built (history in the Securities Report) | The plant that later holds the NAS battery production equipment |
| 2002 | NAS battery for power storage commercialized: the world's first commercialization, the company says | Developed jointly with Tokyo Electric Power Company as a means of closing the gap between day and night power demand, the company explains (date of development not given) |
| 2019 | Collaboration with BASF begins (as stated in the October 2025 disclosure) | Aimed at better performance and lower cost of the battery technology, and a stronger global sales network |
| 2020 to 2023 | Projects such as a hydrogen production plant in Korea (August 2020), renewables in Korea (April 2023), an Australian mine (May), desalination in the Maldives (ordered July) and Bulgaria (September) | Overseas uses were widening, for stabilizing renewables, hydrogen production and more |
| October 2024 | Sales of the improved "NAS MODEL L24" begin. 36 containers shipped to HH2E under the BASF project (as of October) | The company says product improvements for large-capacity, long-duration charge and discharge were complete |
| November 2024 | HH2E (Germany) files for a restructuring procedure after its largest shareholder withdraws further funding (the company's explanation) | Orders for the second lot of the project were cancelled |
| March 2025 | Part of the Komaki Plant temporarily shut down. Inventory written down in the results for the year to March 2025 | A review of production to match slowing demand |
| September 2025 | Talks with BASF on expanding supply capacity and cutting cost are halted | In the company's explanation, one of the factors behind the decision to end NAS batteries |
| 31 October 2025 | The board decides to end NAS battery manufacture and sales and to take no new orders. An extraordinary loss of ¥11.7 billion is booked in the second quarter | The final shipment is planned for around January 2027 |
| March to April 2026 | A business restructuring expense of ¥19,959 million is booked in the year to March 2026 (provision ¥12,270 million). The company is renamed NGK Corporation on 1 April 2026 | The cost of ending the business is fixed, and the shift in business mix proceeds |
7. What comes next
(planned)Orders already taken are shipped and delivered in turn from inventory
operating profit ¥4.0 billionThe company's outlook. It describes the effect of NAS batteries as negligible
The final shipment date and the fiscal 2026 outlook are the company's plan and outlook, not settled results Not yet confirmed. The company plans to reassign the employees who worked on NAS batteries within the group.
None of the following appears in the primary sources we reviewed Not yet confirmed.
The cumulative installed base of NAS batteries (output, capacity, units, countries) / the scale of equipment now operating and the remaining service life by customer / the amounts behind the provision, and the quantity, method and timing of inventory disposal / production capacity of the Komaki Plant for NAS / what happens to NAS technology, equipment and patents (any transfer or reuse in other fields) / the status of other storage batteries such as the zinc secondary battery "ZNB" / results for NAS batteries alone. Press-reported figures are not used here.
8. What the company is aiming for in energy storage
This section includes points the company has not stated directly. They are inferences from what the primary sources say, and each is given with its basis.
| What can be read from it | Primary-source basis | Category |
|---|---|---|
| Ending the NAS battery is a decision about optimal allocation of management resources | In its October 2025 results briefing the company said it decided to end NAS battery manufacture and sales "from the viewpoint of optimally allocating management resources". Its May 2026 long-term plan says it will concentrate funds and people on semiconductor-equipment ceramics and electronic devices as growth drivers | Sourced |
| In power, it will take part through insulators and engineering, not batteries | In April 2026 it set up an Energy Plant division to strengthen engineering and construction for power utilities. It expects stable earnings from insulators on the back of new and expanded transmission investment | Sourced |
| It is exploring other forms of business for stable operation of renewables | The new-business target "NV1000" lists a "green energy business that contributes to stable operation of renewable energy". We could not find details | Sourced (item only) / Inference |
| Potential long-duration demand remains, but NGK alone could not carry it | In April 2025 the company said potential long-duration storage demand was large, and was in talks with BASF and other companies it hoped to bring in on expanding supply capacity. The talks were halted in September | Inference |
The company gave four reasons on 31 October 2025 Sourced. (1) Talks with BASF on expanding supply capacity and cutting cost were halted in September 2025. (2) Building continuing demand for long-duration, large-capacity storage is still expected to take time. (3) Component costs have surged (the document does not say which components). (4) Competition with lithium-ion batteries has intensified. Before these, in the year to March 2025, the second lot of the HH2E project ordered through BASF was cancelled, part of the Komaki Plant stopped, and inventory was written down. In April 2025 the company said it expected "a considerable business scale" and was continuing talks with BASF and others; five months later, in September, those talks were halted, and in October the end was decided. From this we read that the closing of the path to the "next stage" of expanding supply capacity was what decided the end Not yet confirmed (the sequence is fact, but the causal link is our inference and is not what the company says). The company does not blame any particular firm or customer.
9. Map of partnerships in next-generation energy storage
10. Technologies, products and services
As the company describes it, the NAS battery is as follows Sourced. It uses sodium (Na) as the negative electrode and sulfur (S) as the positive electrode, with fine ceramics as the electrolyte separating the two. On discharge, sodium at the negative electrode gives up electrons to become sodium ions, which pass through the solid electrolyte to the positive electrode and react with sulfur to form sodium polysulfide (Na₂Sx). Charging reverses the reaction. As of 2026 it is a product whose sales have ended, and no new orders are taken.
| Item | What official materials say | Note |
|---|---|---|
| Features (manufacturer's stated) | Large capacity, high energy density, long life. About one third the size of a lead-acid battery, giving stable power supply over a long period. It is said to help with peak cut and stabilizing renewable energy | The conditions of comparison (capacity, lead-acid battery type) are not given, so this article does not rank it against other batteries |
| Safety standard | The company says the container-type NAS battery (and the cells and modules in it) has UL certification to UL1973, a safety standard for stationary batteries | As the company's note says, the certification covers the container type only |
| Standard system (container type) | Rated output 800 kW, rated capacity 4,800 kWh. Battery and control equipment in a 20-foot container | Discharge time at rated output is 6.0 hours Our calculation (4,800 kWh ÷ 800 kW) |
| Standard system (package type) | Rated output 1,200 kW, rated capacity 8,640 kWh. Assembled on site | By the same calculation, 7.2 hours Our calculation (8,640 kWh ÷ 1,200 kW) |
| Improved "NAS MODEL L24" | A type co-developed with BASF Stationary Energy Storage GmbH that improves on the earlier container type. The company says less than 1% annual degradation and longer charge and discharge times can cut investment by about 20% (October 2024) | No test conditions are given; this is the company's explanation, not a measurement |
| Maintenance and inspection | Daily inspection (monitoring in normal operation), periodic inspection (replacing consumables such as fans and filters, function tests) and statutory inspection under the Fire Service Act (including keeping open space, once a year). Remote monitoring by the NGK-NAS call centre | As of 2026 the service contact for maintenance remains in place |
What marks the NAS battery is that its electrolyte is a solid fine ceramic, which separates the sodium of the negative electrode from the sulfur of the positive electrode Sourced. This ties in with the company's Securities Report, which names material and process technology centred on fine ceramics as the basis of its R&D. In general, in a battery of this kind the ceramic electrolyte must pass sodium ions only and block electrons and reactants, and whether crack-free, defect-free parts can be made stably in volume largely decides quality and cost. A battery that uses sodium and sulfur is also commonly one operated at high temperature (the foregoing is our own general explanation).
The company cites "a surge in component costs" as one reason for ending, but does not say which components rose in cost. Whether the volume-production cost of the ceramic electrolyte was an issue could not be confirmed from primary sources Not yet confirmed. This article also makes no claim about its performance or cost relative to lithium-ion batteries.
11. The risks this company carries
| Risk | What it involves | Category |
|---|---|---|
| Uncertainty in estimating further costs | In the year to March 2026 the company set up a provision for business restructuring of ¥12,270 million. It mainly covers handling inventory that must be disposed of under relevant laws, and the cost of services it must provide. The auditor lists as a key audit matter the uncertainty in disposal unit costs and in estimates of the future service life of NAS batteries and staffing for services. The company's note says a change in laws, price trends or disposal methods could require an additional provision | Sourced |
| Long-term service for delivered equipment | The company says it will continue after-sales service for products delivered and still to be delivered, responsibly. The provision assumes that the remaining specified service life of each NAS model is the customer's future period of use, which can change with how customers use the batteries | Sourced |
| Effect on customers and suppliers | The company says it will explain the policy carefully to customers and suppliers and, as needed, hold discussions. Orders already taken proceed after confirming the customer's wishes. We could not confirm the content of discussions with individual customers | Sourced / not found |
| Counterparty credit risk | The HH2E (Germany) project ordered through BASF: the company filed for a restructuring procedure in November 2024 and orders for the second lot were cancelled. The company says this led to a partial shutdown of the Komaki Plant and an inventory write-down | Sourced |
| Competition in long-duration storage | The company cites intensified competition with lithium-ion batteries and rising component costs as reasons for ending. It also says the potential demand for long-duration storage itself is large, so how to judge the outcome of the competition needs separate consideration | Sourced |
| Handing on technology and know-how | Apart from reassigning employees, what happens to NAS battery technology, equipment, patents and people could not be confirmed | Not yet confirmed |
| Carrying out the restructuring | The company says it has introduced, from fiscal 2026, a process for reviewing the revival or withdrawal of unprofitable businesses, to make its response clear. The scope of judgment could widen beyond NAS batteries, but we could not confirm any specific target | Inference |
12. Glossary
- NAS battery
- A storage battery with sodium (Na) and sulfur (S) electrodes and a solid ceramic electrolyte. A registered trademark of NGK.
- Sodium-sulfur battery
- The generic name for the NAS battery. Sodium negative electrode, sulfur positive electrode.
- LDES
- Long-duration energy storage: storing electricity for several hours or longer.
- Fine ceramics
- High-performance ceramics made from precisely controlled raw materials and processes. NGK's core materials technology.
- UL1973
- One safety standard for stationary batteries. NGK says its container-type NAS battery has UL certification to it.
- Provision for business restructuring
- A liability booked in advance for costs or losses expected from ending a business or similar action.
- Extraordinary loss
- A loss arising in that period apart from ordinary business activity. Here it is booked as a business restructuring expense.
- BASF
- A large German chemical company. Its subsidiary BASF Stationary Energy Storage GmbH was the partner for NAS battery co-development and sales.
- HH2E
- A German green-hydrogen company and the customer that ordered NAS batteries through BASF.
- Securities Report
- The annual report that listed companies in Japan file under the Financial Instruments and Exchange Act.
13. References
- NGK 160th Securities Report (1 April 2025 to 31 March 2026, filed 22 June 2026), in Japanese. History, segment sales and results, Energy Storage sales, employees, R&D, capital expenditure, business restructuring expense and provision, key audit matters, name change. https://ssl4.eir-parts.net/doc/5333/yuho_pdf/S100YF7M/00.pdf
- NGK Insulators (now NGK) Notice on ending manufacture and sales of NAS batteries (31 October 2025, TDnet), in Japanese. Reasons, schedule, policy, effect on results. https://ssl4.eir-parts.net/doc/5333/tdnet/2705281/00.pdf
- NGK Products and technology: NAS batteries (sales ended), in Japanese. Principle, features, UL1973, standard systems, maintenance. https://www.ngk.co.jp/product/nas.html
- NGK Insulators (now NGK) Results briefing for the first half of the year to March 2026 (31 October 2025), slides and speaker notes, in Japanese. Background to ending NAS batteries, extraordinary loss, Energy & Industry outlook. https://www.ngk.co.jp/ir/library/assets/pdf/20251031_presen_note.pdf
- NGK Results briefing for the year to March 2026 (30 April 2026), slides and speaker notes, in Japanese. NAS-related expense, outlook for the year to March 2027, setting up the Energy Plant division. https://www.ngk.co.jp/ir/library/assets/pdf/20260430_presen_note.pdf
- NGK Insulators (now NGK) Results briefing for the year to March 2025 (28 April 2025), slides and speaker notes, in Japanese. HH2E project, partial shutdown of the Komaki Plant, state of talks with BASF. https://www.ngk.co.jp/ir/library/assets/pdf/20250428_presen_note.pdf
- NGK Insulators (now NGK) Results briefing for the first half of the year to March 2025 (31 October 2024), slides and speaker notes, in Japanese. NAS MODEL L24, shipments to HH2E, overseas sites. https://www.ngk.co.jp/ir/library/assets/pdf/20241031_presen_note.pdf
- NGK Long-Term Management Plan 2026-2035 (28 May 2026), in Japanese. Business portfolio, introduction of the revival or withdrawal review process. https://www.ngk.co.jp/ir/library/assets/pdf/20260528_management_plan.pdf
- NGK Official website (source of the logo), in Japanese. https://www.ngk.co.jp/
14. Claim-to-source audit
| Claim in the article | Category | Source |
|---|---|---|
| Legal name (NGK Corporation, formerly NGK INSULATORS), the 1 April 2026 change of name, head office and filing of the 160th term (22 June 2026) | Sourced | Reference 1 https://ssl4.eir-parts.net/doc/5333/yuho_pdf/S100YF7M/00.pdf |
| Consolidated net sales (¥619,513 million to ¥670,125 million), operating profit (¥81,241 million to ¥94,997 million), R&D of ¥31,786 million, capex (¥48,807 million to ¥55,848 million), employees (19,931 to 19,869; Energy & Industry 1,307) | Sourced | Reference 1 https://ssl4.eir-parts.net/doc/5333/yuho_pdf/S100YF7M/00.pdf |
| Energy & Industry sales (¥57,553 million to ¥65,253 million) and result (-¥4,196 million to -¥1,322 million), Energy Storage (¥6,473 million to ¥11,772 million) and insulators (¥51,080 million to ¥53,481 million) | Sourced | Reference 1 https://ssl4.eir-parts.net/doc/5333/yuho_pdf/S100YF7M/00.pdf |
| Energy & Industry R&D of ¥724 million and capex of ¥2,752 million, NAS production equipment at the Komaki Plant, the plant built in 1962, and commercialization of the NAS battery in 2002 | Sourced | Reference 1 https://ssl4.eir-parts.net/doc/5333/yuho_pdf/S100YF7M/00.pdf |
| Business restructuring expense of ¥19,959 million, provision of ¥12,270 million, its content and the key audit matter | Sourced | Reference 1 https://ssl4.eir-parts.net/doc/5333/yuho_pdf/S100YF7M/00.pdf |
| The decision to end (31 October 2025), the four reasons, the halt of talks with BASF (September 2025), the first commercialization in 2002, the collaboration with BASF from 2019, the final shipment (around January 2027), reassignment of employees, the expected loss of about ¥18 billion, and Energy Storage sales of ¥6,473 million (1.04% of consolidated) in the year to March 2025 | Sourced | Reference 2 https://ssl4.eir-parts.net/doc/5333/tdnet/2705281/00.pdf |
| Principle and features of the NAS battery, UL1973 (container type only), standard system specifications (800 kW/4,800 kWh; 1,200 kW/8,640 kWh), maintenance, joint R&D with Tokyo Electric Power, and the sales-ended notice | Sourced | Reference 3 https://www.ngk.co.jp/product/nas.html |
| October 2025 briefing: ¥11.7 billion extraordinary loss in the second quarter, the end as optimal allocation of resources, Energy & Industry outlook | Sourced | Reference 4 https://www.ngk.co.jp/ir/library/assets/pdf/20251031_presen_note.pdf |
| April 2026 briefing: ¥20.0 billion restructuring expense, the Energy & Industry outlook for the year to March 2027 (sales ¥65.0 billion, operating profit ¥4.0 billion), Energy Storage limited to existing orders and after-sales service, the new Energy Plant division | Sourced | Reference 5 https://www.ngk.co.jp/ir/library/assets/pdf/20260430_presen_note.pdf |
| April 2025 briefing: partial shutdown of the Komaki Plant (March 2025), the cancelled second lot of the HH2E project, HH2E's restructuring filing (November 2024), inventory write-down, talks with BASF and others, and an expected increase in mainly domestic shipments | Sourced | Reference 6 https://www.ngk.co.jp/ir/library/assets/pdf/20250428_presen_note.pdf |
| October 2024 briefing: NAS MODEL L24 (co-developed with BASF Stationary Energy Storage GmbH), under 1% annual degradation and about 20% lower investment (company explanation), 36 containers to HH2E, and overseas sites | Sourced | Reference 7 https://www.ngk.co.jp/ir/library/assets/pdf/20241031_presen_note.pdf |
| Long-Term Management Plan 2026-2035: growth drivers are semiconductor-equipment ceramics and electronic devices, introduction of the revival or withdrawal review process, and the new-business target NV1000 | Sourced | Reference 8 https://www.ngk.co.jp/ir/library/assets/pdf/20260528_management_plan.pdf |
| Results for NAS batteries alone, production capacity, cumulative installed base, the quantity and timing of inventory disposal, the future of the technology and patents, the status of ZNB and other batteries, and any government subsidy or university joint research | Not yet confirmed | References 1, 2, 3, 5 https://ssl4.eir-parts.net/doc/5333/yuho_pdf/S100YF7M/00.pdf https://ssl4.eir-parts.net/doc/5333/tdnet/2705281/00.pdf https://www.ngk.co.jp/product/nas.html https://www.ngk.co.jp/ir/library/assets/pdf/20260430_presen_note.pdf |
| The four-type classification (cells & materials, long-duration & new chemistries, storage systems, recycling) and NGK's position (long-duration & new chemistries) | Our calculation | Our own classification; company names are examples from those covered in this series |
| Energy Storage as a share of consolidated sales for the year to March 2026 (about 1.76%) | Our calculation | Our own calculation, 11,772 ÷ 670,125 (¥ million) |
| Discharge time of the standard systems (6.0 hours for the container type, 7.2 hours for the package type) | Our calculation | Our own calculation of rated capacity ÷ rated output; actual discharge conditions will differ |
| The reading that the halt of talks with BASF decided the end | Inference | Our own reading of the sequence (talks under way in April 2025, halted in September, end decided in October); not what the company says |
| The reading that NGK alone could not carry the expansion of supply capacity | Inference | Our own reading of the course of the talks |
| The reading that it is exploring another form of business for stable operation of renewables | Inference | Our own reading of the NV1000 item alone |
| The reading that withdrawal decisions could extend beyond NAS batteries | Inference | Our own reading of the introduction of the revival or withdrawal review process |
| The properties required of a ceramic electrolyte, and that such batteries are commonly run at high temperature (general points) | Our calculation | This is our own general commentary and not performance values published by NGK |
Last updated 10 October 2026 / Troy Technical
Figures in this article come from NGK's (formerly NGK Insulators') Securities Report, timely disclosures, results briefing materials and official website. No research-firm estimates or press-reported figures have been used. Items marked "Inference" are our reading of the primary sources and are not statements by the company. The company's plans and outlook are not yet confirmed and are not results achieved. Fires and accidents are not covered in this article.