Redwood Materials, a US-based battery energy storage manufacturer and recycling firm, has closed a $425 million Series E funding round backed by Google.

The company said that it would use the proceeds to accelerate its energy storage platform while continuing to strengthen its integrated recycling and critical minerals business. The Series E funding round also included Nvidia’s venture capital arm NVentures.

Founded in 2017 and based out of Carson City, Nevada, Redwood Materials recycles lithium-ion batteries and manufactures battery-grade materials such as lithium, nickel, cobalt, and copper. The company, started by Tesla co-founder JB Straubel, aims to build a closed-loop supply chain for electric vehicles and energy storage batteries.

In June of last year, the company launched Redwood Energy as a new business division focused on repurposing used EV batteries into large-scale energy storage systems for grid and industrial use, with a particular focus on AI data centers.

As part of the launch, the company partnered with data center developer Crusoe to develop a microgrid system for the company’s data center portfolio. The companies have already deployed the 12MW/63GWh microgrid at an undisclosed Crusoe AI data center, where Crusoe is pioneering its Spark modular AI data center solution.

Redwood is not the first battery storage company to gain backing from Google. Last year, the search giant made its first foray into the long-duration energy storage (LDES) market, inking a deal with CO2 battery developer Energy Dome.

In September, the company announced that it would support the deployment of LDES technology as part of a demonstration project with the Arizona public power utility, Salt River Project (SRP)

Google is not the only data center company to throw its backing behind LDES. In May, Prometheus Hyperscale signed a deal with XL Batteries, an organic flow battery developer, to supply and install a 333kW demonstration-scale battery at an undisclosed Prometheus site in 2027. Following this, Prometheus plans to acquire a 12.5MW/125MWh commercial-scale system in 2028, with another identical system to follow in 2029.

However, concerns still permeate the LDES sector. Earlier this month, sodium-ion battery manufacturer Natron Energy was forced to shutter its operations due to insufficient funding.