# Metal-air batteries: What to track

Real efficiency, real costs and whether deliveries keep pace

Source page: https://www.materialinsights.org/energy/e_metal_air/tracking/

What this tab covers The attributes worth tracking regularly, with the latest value, the direction of travel and why each matters.

Track whether Form's first systems meet their efficiency and cycling claims, the real cost per kWh, and progress of aluminium-air manufacturing in India.

| Category | Attribute | Latest | Trend | Why it matters |
|---|---|---|---|---|
| Techno-economic | **LCOS trajectory** | No published LCOS; Form cost target USD 20/kWh, current cost undisclosed (2026)^[1](https://www.technologyreview.com/2026/10/06/1145020/2026-climate-tech-companies-to-watch-form-energy-iron-batteries/amp/) | → stable | Cost per MW of firm capacity versus a gas peaker is the more useful yardstick. |
| Technical | **Capacity fade and state of health** | Over 80% capacity after more than 1,000 cycles (Form company figure); no field data yet^[1](https://www.technologyreview.com/2026/10/06/1145020/2026-climate-tech-companies-to-watch-form-energy-iron-batteries/amp/)^[2](https://www.energy-storage.news/100-hour-ldes-battery-technologies-from-form-noon-and-ore-how-do-they-compare/) | → stable | Field data from the Great River Energy system, still being completed in late 2026, will be the first real test. |
| Supply chain | **Critical mineral cost and geopolitical concentration** | Iron abundant; China about 32% of zinc and 61% of primary aluminium (calculated, 2025)^[8](https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-zinc.pdf)^[9](https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-aluminum.pdf) | → stable | Iron-air has low mineral risk; aluminium-air inherits aluminium's concentration in China. |
| Market | **Ancillary service market saturation** | Not relevant for 100 h storage; capacity and resource adequacy markets matter^[2](https://www.energy-storage.news/100-hour-ldes-battery-technologies-from-form-noon-and-ore-how-do-they-compare/) | → stable | Value depends on regulators paying for multi-day reliability. |
| Regulatory | **Safety and environmental compliance** | Non-flammable alkaline electrolyte; NFPA 855 permitting in the US; EU lead limit for zinc-air button cells from 18 Aug 2028^[11](https://www.sgs.com/en/news/2023/09/safeguards-11523-eu-issues-new-regulation-on-batteries-and-waste-batteries) | → stable | Low fire risk eases siting compared with lithium-ion. |
| Environmental | **Lifecycle carbon payback period** | No figure found in sources reviewed | → stable | Low efficiency raises the carbon cost if charging power is not clean. |
| Technical | **Round-trip efficiency (technology-specific)** | Iron-air 35-38% (Form presentations 2021-2023), about 40% (LinkedIn commentator); not independently verified^[2](https://www.energy-storage.news/100-hour-ldes-battery-technologies-from-form-noon-and-ore-how-do-they-compare/) | → stable | Every point of efficiency cuts charging cost per MWh delivered. |
| Corporate | **Manufacturing scale-up versus backlog (technology-specific)** | 2 GWh a year factory against an 80 GWh backlog; USD 750 million raised Aug 2026 to expand Weirton^[1](https://www.technologyreview.com/2026/10/06/1145020/2026-climate-tech-companies-to-watch-form-energy-iron-batteries/amp/)^[16](https://www.energy-storage.news/iron-air-us-ldes-startup-form-energy-secures-us750-million-series-g-financing/) | ↕ volatile | Delivery risk is the main near-term risk; the lower reported valuation shows investor caution. |

#### Sources

1. [15 Climate Tech Companies to Watch 2026: Form Energy (6 Oct 2026)](https://www.technologyreview.com/2026/10/06/1145020/2026-climate-tech-companies-to-watch-form-energy-iron-batteries/amp/) MIT Technology Review, 2026
2. [100-hour LDES battery technologies from Form, Noon and Ore: how do they compare? (cites Form presentations and a LinkedIn commentator)](https://www.energy-storage.news/100-hour-ldes-battery-technologies-from-form-noon-and-ore-how-do-they-compare/) Energy-Storage.news, 2025
3. [Mineral Commodity Summaries 2026: Zinc](https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-zinc.pdf) US Geological Survey, 2026
4. [Mineral Commodity Summaries 2026: Aluminum](https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-aluminum.pdf) US Geological Survey, 2026
5. [SafeGuardS 115/23: EU issues new regulation on batteries and waste batteries (summary of Regulation (EU) 2023/1542)](https://www.sgs.com/en/news/2023/09/safeguards-11523-eu-issues-new-regulation-on-batteries-and-waste-batteries) SGS, 2023
6. [Iron-air US LDES startup Form Energy secures US$750 million Series G financing (Aug 2026)](https://www.energy-storage.news/iron-air-us-ldes-startup-form-energy-secures-us750-million-series-g-financing/) Energy-Storage.news, 2026

## Other sections

- [Summary](https://www.materialinsights.org/energy/e_metal_air/index.md)
- [Overview](https://www.materialinsights.org/energy/e_metal_air/overview/index.md)
- [Correlation](https://www.materialinsights.org/energy/e_metal_air/correlation/index.md)
- [Science and technology](https://www.materialinsights.org/energy/e_metal_air/sg-sci/index.md)
- [Engineering and performance](https://www.materialinsights.org/energy/e_metal_air/sg-eng/index.md)
- [Economics](https://www.materialinsights.org/energy/e_metal_air/sg-econ/index.md)
- [Impact and additionality](https://www.materialinsights.org/energy/e_metal_air/sg-impact/index.md)
- [Relationships](https://www.materialinsights.org/energy/e_metal_air/links/index.md)