For decades, we’ve never truly needed massive, grid-scale energy storage systems. Energy was produced, (occasionally) transported, and then consumed shortly after. That’s because with traditional energy sources, the energy is simply “stored” as raw fuel—such as coal or oil—until it’s ready to be used. The plant then burns the fuel to generate electricity, which is sent to the grid on-demand. However, the global push toward clean and renewable energy has introduced a new critical component to the energy ecosystem: advanced energy storage. These technologies aim to address the intermittency issue of renewable sources like solar and wind. In this guide, we’ll explore the top energy storage stocks, split into technology categories ranked by disruptive potential.

Note: We make every effort to keep our info accurate and up-to-date. However, emerging tech moves fast and company situations can change overnight. This guide is an intro to the energy storage market; but ultimately, do your own due diligence before taking action.

Major Growth Drivers Behind Energy Storage Technology

Renewable energy sources are inherently intermittent. When the sun doesn’t shine or when the wind doesn’t blow, solar and wind sources dry up. Energy storage technologies aim to address this issue by capturing excess energy during peak generation times—such as sunny afternoons or windy nights—and releasing it when production wanes. This decouples energy supply from demand, which is critical for grid stability and resilience.

Thus, one the primary drivers of the energy storage market is the global push toward renewable energy. The cost of renewables decrease year after year, while governments around the world are implementing supportive policies (e.g., The Inflation Reduction Act, the Paris Climate Accord, etc.). Since 2000, solar and wind capacity have grown by 417,800% and 63,380% respectively. During the same period, fossil fuel consumption increased by only 68.9%.

The other major driver of the energy storage market is electric vehicle (EV) adoption. Current lithium-ion batteries, while much improved, still have lower energy density than fossil fuels. This limits the range of EVs and the amount of energy that can be stored in a given volume or weight. Plus, even with fast-charging technologies, EVs still take longer to “refuel” than conventional vehicles. As more people switch to EVs, the demand for high-capacity, long-lasting batteries naturally increases hand-in-hand. From these perspectives, energy storage stocks can thus be seen as a “backdoor” way to invest in the renewable energy or the EV markets.

Limitations of Current Lithium-Ion Technology

Despite their widespread use in everything from smartphones to electric vehicles, lithium-ion batteries face several key limitations when it comes to scalability. For example, lithium-ion batteries have notable safety issues when deployed at scale. Thermal runaway, a condition where the battery overheats uncontrollably, can quickly spiral into fires or explosions. This has led to high-profile incidents like the 2019 explosion at an energy storage facility in Arizona. Lithium-ion batteries also degrade over time, with capacity typically declining by about 20% after 1,000 full charge-discharge cycles, limiting their lifespan to around 7-10 years for stationary applications.

To overcome these limitations, the industry is exploring a range of alternative energy storage technologies. Three stand out potentially true stepwise breakthroughs in energy storage:

  1. Solid-state batteries aim to improve safety and energy density by replacing flammable liquids with solid electrolytes.
  2. Flow batteries use large electrolyte tanks that degrade much slower and can be used for utility-scale storage.
  3. Green hydrogen is converted from excess renewable energy via electrolysis and can be stored indefinitely

For investors, understanding the nuances of each technology is crucial. The energy storage market is not a one-size-fits-all landscape; different applications may favor different technologies based on factors like duration, capacity, cost, and safety. For instance, residential energy storage might prioritize safety and cost, while utility-scale storage might prioritize long-duration capabilities.

EV Battery Diagram
Electric vehicle (EV) adoption is one of the main drivers of energy storage technology.

Tier 1: Solid-State Batteries

Solid-state batteries are the most exciting and potentially game-changing energy storage technology, especially for applications that prioritize safety and energy density, such as EVs and grid storage. The idea here is simple in theory but difficult to implement: replace the liquid electrolyte in conventional lithium-ion batteries with a solid electrolyte instead. This not only leads to much higher energy densities—up to 2-3 times more—but also greater safety due to the elimination of flammable liquids. Some companies have already built functional solid-state batteries, but manufacturing them at scale remains a major hurdle due to high production costs and technical complexities. These energy storage stocks have large upside, but also major near-term hurdles to overcome.

Note: For a broader view of solid-state battery technology, please see our dedicated guide on solid-state battery stocks.

QuantumScape (NYSE: QS)

QuantumScape (QS) is a leader in developing solid-state lithium-metal batteries for EVs. Their proprietary solid ceramic electrolyte significantly increases energy density compared to conventional lithium-ion batteries. QuantumScape’s released performance data shows that its single-layer cells could charge from 0 to 80% capacity in just 15 minutes, operate at a wide range of temperatures (-30°C to 60°C), and last over 800 charge cycles while retaining more than 80% of their capacity. QuantumScape has a strategic partnership with Volkswagen Group, which has invested over $300 million and plans to incorporate QuantumScape’s batteries into its EVs. 

Solid Power (NASDAQ: SLDP)

Solid Power (SLDP) specializes in all-solid-state rechargeable batteries for electric vehicles and other applications. The company’s batteries use sulfide-based solid electrolytes for higher energy density and enhanced safety. Solid Power has partnerships with major automakers, including Ford Motor Company and BMW, both of which have invested in the company and entered into joint development agreements. Solid Power aims for commercial production by 2026.

Toyota Motor (NYSE: TM)

Toyota (TM), the global automotive leader, has been investing in solid-state battery research for over a decade. The company holds more than 1,000 patents related to solid-state batteries, making it one of the most significant intellectual property holders in the field. In 2020, Toyota unveiled a working prototype vehicle equipped with a solid-state battery, a major step toward commercial viability. Toyota aims to begin mass-producing solid-state batteries by 2027-2028, leveraging its extensive manufacturing expertise and global supply chain.

Ilika plc (LON: IKA)

UK-based Ilika (IKA) focuses on developing solid-state batteries using advanced materials technology. The company’s Stereax technology produces miniature solid-state batteries with high energy density and long life spans, suitable for medical implants, industrial sensors, and IoT devices. Beyond small-scale batteries, Ilika is also advancing its Goliath program to develop large-format solid-state batteries for EVs and grid storage. Ilika has collaborated with industry partners and received funding from government agencies to accelerate development.

Green hydrogen could become the answer to large-scale, long-duration storage.

Tier 2a: Green Hydrogen

Hydrogen energy storage offers the potential for large-scale, long-duration storage. It enables seasonal storage, balancing supply and demand over longer periods than batteries can manage. Basically, excess renewable energy can produce green hydrogen via electrolysis, which can then be stored indefinitely and used for power generation, transportation, or industrial processes. Currently, the round-trip efficiency of hydrogen storage is still relatively low, around 30-40%, due to losses during electrolysis and transport (versus 80-90% for battery storage). The success of these energy storage stocks will also depend on the development of infrastructure for hydrogen transport and storage, which is currently underdeveloped.

Plug Power Inc. (NASDAQ: PLUG)

Plug Power (PLUG) specializes in hydrogen fuel cell systems that replace conventional batteries in equipment and vehicles. The company is expanding its focus to become a fully integrated green hydrogen provider, covering production, storage, and distribution. To do so, Plug Power is constructing a network of green hydrogen production facilities across the US, boosted by a $1.66 billion conditional commitment loan guarantee from the Department of Energy. By controlling the entire value chain, Plug Power aims to optimize efficiency and reduce costs to position itself as a leader in the green hydrogen economy.

Nel ASA (OSE: NEL)

Norway-based Nel ASA (NEL.OL) is a global hydrogen company specializing in the production, storage, and distribution of hydrogen from renewable energy. Founded in 1927, Nel has decades of experience in hydrogen technologies. In June 2024, Nel completed the spin-off of its fueling station business into Cavendish Hydrogen ASA. That means the company is now solely dedicated to developing and delivering electrolyser technology for green hydrogen production. Nel works with global energy giants to integrate its electrolyzers into large-scale renewable energy projects, aiming to make green hydrogen a viable option for grid-scale energy storage and industrial applications.

ITM Power plc (LON: ITM)

UK-based ITM Power (ITM.L) designs and manufactures PEM electrolyzers for producing green hydrogen. The company operates one of the world’s largest electrolyzer production facilities, the Gigafactory in Sheffield, with an annual capacity of 1 GW. ITM Power’s systems are designed for ease of integration into existing energy infrastructure, making them suitable for grid balancing, energy storage, and refueling. By focusing on scalability and integration, ITM Power aims to drive down the cost of green hydrogen and facilitate its adoption across various industries. 

Bloom Energy (NYSE: BE)

Bloom Energy (BE) is known for its solid oxide fuel cell technology that provides on-site power generation. Leveraging its expertise in solid oxide technologies, the company has expanded into the green hydrogen space by developing high-efficiency electrolyzers. In 2021, the company showed that its electrolyzer could produce hydrogen at an efficiency of over 90% when powered by excess heat and electricity from nuclear or concentrated solar power plants. This high efficiency has the potential to significantly reduce the cost of green hydrogen production. The company is now collaborating with industry leaders, such as Heliogen and Shell, to deploy its electrolyzer technology in large-scale renewable hydrogen projects.

Flow batteries are scalable and stable, but require substantial space due to lower energy density.

Tier 2b: Flow Batteries

Flow batteries, such as vanadium redox and iron-flow batteries, offer the ability to store energy for extended periods, from hours to days. Their capacity can be easily scaled by increasing the size of the electrolyte tanks, making them ideal for utility-scale applications. Flow batteries also do not suffer the same degradation issues of lithium-ion batteries—flow batteries can last 20 years or more with minimal capacity loss. However, they have lower energy density, making them unsuitable for space-constrained applications. The upfront costs are also much higher, as the technology is less mature commercially than lithium-ion batteries.

ESS Inc. (NYSE: GWH)

ESS Inc. (GWH) specializes in iron-flow batteries for long-duration energy storage for utilities, commercial and industrial facilities, and microgrid systems. ESS Tech’s batteries use an all-iron electrolyte, leveraging one of the most abundant and environmentally friendly materials available. This contrasts with vanadium or zinc-bromine used in other flow batteries, reducing material costs and supply chain risks. The batteries are designed for a lifespan of over 25 years with unlimited cycling and minimal capacity fade, significantly outperforming the typical 7-10 years lifespan of lithium-ion batteries in stationary applications.

Invinity Energy Systems plc (LON: IES)

UK-based Invinity Energy Systems (IES.L) is a global leader in vanadium flow battery technology. Utilizing vanadium electrolytes, their batteries have a lifespan of 25 years and can perform unlimited cycles without degradation, making them ideal for daily cycling applications. Invinity’s notable projects include the Energy Superhub Oxford, one of the world’s largest hybrid battery systems combining vanadium flow and lithium-ion technologies. The company is also involved in projects in North America, Australia, and Asia, supporting renewable energy integration and grid services.

Sumitomo Electric Industries Ltd. (TYO: 5802)

Japan-based Sumitomo Electric Industries (5802.T) is a multinational corporation with a broad portfolio spanning electric wires, optical fibers, and energy storage systems. The company has been a pioneer in vanadium redox flow battery (VRFB) technology since the 1980s, focusing on large-scale energy storage solutions for utility applications. Sumitomo Electric has developed some of the world’s largest flow battery installations, including a 60 MWh system on the northern Japanese island of Hokkaido, used for renewable energy stabilization and grid management.

Tier 3: Advanced Lithium-Ion and Other Alternatives

Despite the buzz around emerging energy storage technologies such as solid-state batteries, it’s far too early to write off lithium-ion or other “old” alternatives like zinc-based batteries. While these technologies might not offer the same transformative potential, their incremental gains—combined with their deeply entrenched supply chain and distribution ecosystem—could be enough to stave off any disruptors in the near-term.

The cost of lithium-ion batteries has plummeted by approximately 89% since 2010, making them economically viable for a broader range of applications, including residential and commercial systems. Thus, these energy storage stocks represent a relatively safer bet on the incumbent technology.

Enovix Corporation (NASDAQ: ENVX)

Enovix Corporation (ENVX) designs and manufactures advanced silicon-anode lithium-ion batteries. The company has developed a proprietary 3D cell architecture that enables the use of a 100% active silicon anode, significantly increasing energy density compared to traditional graphite-based lithium-ion batteries. By employing a 3D cell architecture, the company overcomes the challenges associated with silicon anodes, such as volume expansion during charge cycles that can lead to battery degradation. Enovix’s batteries offer energy densities exceeding 900 watt-hours per liter (Wh/L), substantially higher than conventional lithium-ion batteries, which typically range between 500 to 700 Wh/L.

Amprius Technologies, Inc. (NYSE: AMPX)

Amprius Technologies (AMPX) specializes in producing high-energy, high-power lithium-ion batteries using silicon nanowire anode technology. Silicon has a theoretical capacity approximately ten times higher than graphite but expands significantly during charging, causing it to degrade. Amprius’s patented nanowire technology accommodates this expansion without compromising structural integrity, and has led to batteries with nearly double the energy density of conventional lithium-ion batteries. Amprius’s batteries are used in high-altitude pseudo-satellites (HAPS), drones, and aerospace applications where weight and energy density are critical.

Eos Energy Enterprises, Inc. (NASDAQ: EOSE)

Eos Energy Enterprises (EOSE) provides zinc-based energy storage solutions for utility, commercial, and industrial applications. The company’s Znyth® aqueous zinc battery is a low-cost, long-life alternative to lithium-ion batteries for stationary storage. Eos’s technology advantage lies in its zinc hybrid cathode, using abundant and non-toxic materials like zinc and aqueous electrolytes. The Znyth battery operates at ambient temperature, is not prone to thermal runaway, and has a projected lifespan of over 20 years with minimal capacity degradation. It offers a levelized cost of storage competitive with lithium-ion, particularly for long-duration applications.

Nano One Materials Corp. (TSX: NANO)

Canada-based Nano One Materials (NANO.T) focuses on improving performance and cost of cathode materials used in lithium-ion batteries. The company has developed the patented “One-Pot” process. This innovative manufacturing process produces single-crystal cathode powders directly from raw materials in a single reaction. This eliminates multiple steps in traditional cathode manufacturing, reduces waste, and can produce various cathode types, including lithium iron phosphate (LFP) and nickel-rich NMC (nickel-manganese-cobalt).

NeoVolta (NASDAQ: NEOV)

NeoVolta (NEOV) offers residential energy storage systems using lithium iron phosphate (LiFePO₄) batteries, which are safer and have a longer lifespan than traditional lithium-ion batteries. Their systems are designed for easy integration with existing solar installations, targeting homeowners looking for energy independence and protection against grid outages. The residential storage market is highly competitive, with major players like Tesla and LG Chem holding significant market share.