US zinc battery storage manufacturer Eos Energy Enterprises has completed two financing transactions totalling over US$1 billion to strengthen its financial position and fund expansion.
Eos completed its previously announced offering of 1.75% convertible senior notes due 2031, including the full exercise of the initial purchasers’ option to buy extra notes, raising about US$580.5 million in net proceeds.
After exercising the option, US$600 million in aggregate principal of 1.75% convertible senior notes due in 2031 were issued and remained outstanding.
Proceeds from the offerings were allocated to repurchase US$200 million of the company’s 6.75% Convertible Senior Notes due 2030.
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Additionally, the balance sheet was enhanced by approximately US$474 million in cash, after accounting for the offerings, net of initial purchaser discounts and commissions, before deducting expenses.
Eos claims this refinancing “meaningfully enhances its capital structure.”
CEO Joe Mastrangelo noted “the world is entering an energy supercycle,” where long-duration energy storage (LDES) is becoming essential infrastructure.
Unlike lithium-ion batteries that typically provide 1-4 hours of storage, Eos claims its hybrid aqueous zinc cathode systems can cost-effectively store energy for 4-16+ hours.
This could make them ideal for grid stabilisation and renewable energy integration. The company’s Znyth technology utilises readily available, non-precious materials and boasts safety advantages over conventional battery chemistries.
That said, while Eos and providers of other non-lithium electrochemical energy storage, such as flow batteries, are aiming to commercialise their solutions for long-duration energy storage (LDES) applications, some developers, technology providers and industry experts see the falling costs and increasing energy density of lithium-ion (Li-ion) batteries as evidence that Li-ion battery energy storage systems (BESS) can cost-effectively go beyond the 4-hour mark and into 6-hour to 12-hour LDES territory.
Eos announced earlier this week (24 November) it had completed its previously announced registered direct offering of 35,855,647 common stock shares at US$12.78 per share to a select group of investors. Along with the Convertible Notes offering, the transaction generated total proceeds of approximately US$458.2 million.
Eos also issued warrants to the US Department of Energy (DOE) as part of ongoing loan agreement modifications. This occurred while the Trump Administration reviews the Office of Energy Dominance Financing loan portfolio. The arrangement provides Eos with flexibility to seek private funding, while enabling the DOE to benefit from potential equity gains.
Eos says this creates a mutually beneficial situation that enhances the government’s potential returns.
In addition to the financing, during the fourth quarter, about 7 million Eos public warrants were exercised before expiration, contributing roughly US$80.2 million in cash. This, combined with the financing activity, improves the company’s liquidity and supports its progress toward achieving sustained manufacturing scale and commercial success.
In October, Eos announced it would invest US$352.9 million to relocate its headquarters to Pennsylvania from New Jersey.
Its Q2 2025 financial results from 30 July, showed that the company had still not reached profitability.
In November, the company revealed its Q3 2025 financial results. During a shareholder presentation, Eos highlighted an order backlog of approximately US$644.4 million, representing about 2.5GWh of customer orders, and a pipeline of commercial opportunities valued at US$22.6 billion, roughly 91GWh.
The presentation also underscored a healthy cash position, with US$126.8 million available as of the end of Q3.
