Solid-State Batteries in 2025: What’s Actually Available, What’s Semi- | Renogy UK

Solid-state batteries (SSBs) have quickly become one of the biggest talking points in energy storage, largely because they could influence how future batteries are built and how they perform in the real world.

Even so, the industry is still working towards a common definition, and there is currently no single, formal certification that verifies a battery as “solid-state”. In this article, we’ll outline the current SSB landscape, explain why the term is used so broadly, and explore what these developments could mean for Renogy going forward.

Industry Situation: What “Solid-State” Means in Today’s Market

The Simplest Definition

To understand what "solid-state batteries" are, it helps to understand the basics of standard lithium-ion batteries. Simply put, a conventional lithium-ion battery consists of an anode, a cathode, a separator, an electrolyte (typically liquid). During charging, lithium ions move from the positive electrode through the liquid electrolyte and the separator, then settle into the negative electrode. This process reverses during discharge.

"Solid-state batteries," as the name suggests, are a category of batteries that replace this traditional liquid electrolyte with solid or semi-solid materials.

The Key Realities in 2025

When we discuss "solid-state batteries," what are we truly talking about? In most discussions, people instinctively envision the "All-Solid-State Battery" (ASSB), the industry’s "long-term goal." In this ideal form, the battery contains no liquid electrolyte whatsoever, a goal that researchers and manufacturers are eagerly pursuing.

However, it is crucial to distinguish between this conceptual ideal and this current reality. Clarifying this gap helps consumers look past marketing hype and understand what this new technology can actually deliver today.

First, true all-solid-state Batteries are still largely in the R&D phase. They have yet to achieve broad commercial use in electric vehicles (EVs), wearables, or grid-scale storage. According to Marija Maisch of pv magazine, major global manufacturers like Toyota and Nissan remain in the pilot production phase as of 2025, with large-scale manufacturing not expected until 2030. Even Solid Power, a leader in the field, does not anticipate mass production until the second half of 2026.

Consequently, most "solid-state" batteries currently in the consumer market are actually "semi-solid-state." Recent developments from Chinese EV makers highlight this trend. For instance, NIO launched the ET7 in June 2024, with a 150kWh semi-solid-state battery (a hybrid of liquid and solid electrolytes) capable of an estimated 609-mile (981km) range (Tim Levin, 2024). Similarly, SAIC Motor’s MG4, released this September, uses semi-solid-state technology from QingTao Energy (Florian Treiss, 2025). This technical breakthrough allows the battery to pass nail-penetration tests without smoke or flames, helping to eliminate the risk of spontaneous combustion.

Furthermore, the industry is exploring various technical paths to bring solid-state technology to life. Some companies focus on replacing flammable liquid electrolytes with solid materials. QuantumScape, for example, uses oxide ceramics that remain stable during a puncture, preventing the chain reaction of thermal runaway. Meanwhile, CATL is pursuing multiple avenues, including oxides and sulfides, to achieve a technical breakthrough.

Alongside the search for the ideal solid-state electrolyte, some teams are tackling the challenge from another angle: innovating the battery’s cathode and anode materials. Colorado-based Solid Power is a prime example; they use high-silicon anodes to support faster charging and ensure performance in cold temperatures. They are also exploring lithium-metal anodes, which could significantly increase energy density, reducing battery weight while extending the range and efficiency of future EVs.

Why “Solid-State” and “Semi-Solid-State” Are Often Grouped Together

Given the R&D and market realities mentioned above, it is clear why "solid-state battery" has become an umbrella term used throughout the industry and media. There are two primary reasons for this:

Reason 1: Divergent Technical Pathways

Currently, companies and research institutions are pursuing vastly different technical routes based on their specific expertise and market positioning. For example, solid electrolytes range from sulfide to oxide systems. When combined with various anode and cathode materials, this results in a wide array of technical configurations. Furthermore, the industry lacks a consensus on the definition of "solid." One company may label a battery "solid-state" if its liquid content is below 10wt%, while another may insist that it must be entirely liquid-free. This diverse pathways make it impossible to establish a single, unified technical specification.

Reason 2: Incremental Commercialization

A significant engineering gap exists between "all-solid-state" lab prototypes and mass-produced commercial batteries. To bridge this gap, "semi-solid" or "hybrid solid-liquid" batteries have emerged as the most practical, near-term solution for vehicle integration. These transitional solutions retain some liquid electrolyte to address challenges such as ionic conductivity and high interfacial impedance. Regardless of whether a battery is "all-solid-state" or "semi-solid-state," the shared goal is clear: to gradually reduce, and eventually eliminate, flammable liquid electrolytes that lead to lithium dendrite growth.

Why There’s No “Official Stamped Solid-State Certification” Today

When shopping for a new refrigerator or washing machine, people often look for the "Energy Star" label to verify energy efficiency. Since the debut of solid-state battery products, consumers have frequently asked if there is a similar official "stamp of approval" for solid-state technology. Unfortunately, no such industry-wide certification exists yet. This is simply because R&D paths are so diverse that the industry has not yet settled on a unified definition or set of testing conditions. As all-solid-state batteries move into true mass production, standardized definitions and certifications will follow.

However, the absence of an SSB-specific certificate does not mean these products lack safety credentials. Take Renogy’s solid-state batteries, for example: before they ever leave the factory, they must pass the same rigorous testing as any traditional battery. They are fully certified under standards such as CE, FCC, RoHS, R10, and UN38.3, ensuring complete safety during both transport and everyday use.

The Benefits of Solid State

As major EV brands and research teams invest heavily in solid-state batteries (SSBs), a practical question comes up again and again: what will this technology actually change in day-to-day use? The clearest way to look at it is through three areas people care about most: safety, energy density, and cycle life.

Safety

Most conventional lithium batteries use a liquid electrolyte to move ions between the anode and cathode, which is how the battery stores and delivers power. If something goes wrong, such as a short circuit, overcharging, or physical damage, heat can build rapidly. In severe cases, that heat escalation can trigger thermal runaway, where the electrolyte becomes a fuel source, and the event can progress into fire or even an explosion.

Solid-state technology aims to reduce that risk by replacing flammable liquid electrolytes and relying more on non-combustible electrolyte materials such as ceramics or polymers (often alongside a different approach to separation). In simple terms, it is like removing a major accelerant from the system. In theory, this can improve stability in abusive conditions, including puncture scenarios, high-impact events, or overcharge testing.

That said, it is important to keep expectations grounded. Moving towards solid electrolytes can improve safety potential, but it is not a magic switch that makes any battery “perfectly safe”. Real-world battery safety still depends on the full system: strong mechanical design, an intelligent BMS, protective circuitry, and proper customer use.

Energy Density

Simply put, energy density measures how much energy a battery can store relative to its weight or volume. The higher the energy density, the further an electric vehicle can travel, or the longer a smartphone can stay powered on a single charge.

In traditional liquid-based batteries, common chemistries like graphite and lithium cobalt oxide (LCO) are widely used, but they offer relatively limited energy density. Solid-state cell designs, however, unlock the potential for higher-capacity electrode materials, such as lithium-metal anodes.

Lithium metal is difficult to use in liquid systems due to safety and stability concerns, but solid-state designs may offer a more stable alternative. That said, the energy density an all-solid-state battery can achieve depends on the specific materials and cell engineering each company uses.

Longevity

When we talk about how long a battery lasts, it usually comes down to two ideas: cycle life and long-term stability. Cycle life is the number of complete charge–discharge cycles a battery can deliver before its capacity falls to a set level (often around 80% of its original capacity). Long-term stability describes how well the battery holds up over time under different real-world conditions. A few key factors have the biggest impact on overall lifespan:

Depth of Discharge (DoD):Taking a battery from 100% down to 0% repeatedly causes far more wear than partial cycling (for example, using it between 90% and 30%). In general, shallower cycles are kinder to the battery over time. For lead-acid users, a common best practice is to keep DoD at 50% or less.
Temperature: Extreme temperatures can shorten battery life. High heat is often the biggest driver because it speeds up internal reactions that age the cell. Very cold conditions can also reduce performance. In traditional lithium batteries, charging or operating in low temperatures can encourage lithium dendrite formation, tiny needle-like structures that may damage internal layers and increase the risk of faults.
Charge and discharge rates: Regular “ultra-fast” charging or sustained high-power discharge places extra strain on the cell chemistry, which can reduce service life over time.

In theory, solid-state designs can offer durability advantages because the internal structure is more stable and may reduce unwanted side reactions. Just as importantly, a solid electrolyte can help limit lithium dendrite growth, which is one reason the technology is being pursued for longer cycle life and stronger long-term stability.

Renogy’s Solid-State Approach

What Renogy Means When We Say “Solid-State”

Renogy has taken a practical “middle-ground” approach. The hybrid solid–liquid cells we adopt use oxide–polymer solid materials to significantly reduce the amount of liquid electrolyte inside the battery.

Compared to traditional lithium-ion batteries (typically 25%–35% liquid by weight), Renogy’s semi-solid cells reduce liquid content by about 70%, bringing it down to roughly 10% by weight. With more solid material in the cell, thermal resistance improves, so the battery’s temperature rises more slowly. Even when heat continues to build, the risk of thermal runaway is greatly reduced. Furthermore, the cathode and anode of these hybrid cells are coated with a high-melting-point solid-state electrolyte that withstands temperatures up to 572°F (300°C).

In the event of external impacts or punctures, the cell remains stable and resists ignition or explosion. This technical breakthrough provides a major safety upgrade for users in demanding, off-grid environments, such as RVing and marine applications, where reliability is paramount.

Why Combine This Approach with LiFePO4 (LFP)

Beyond semi-solid electrolytes, Renogy uses Lithium Iron Phosphate (LFP), a market-proven chemistry celebrated for its stability and high energy density compared to lead-acid alternatives.

Safety is further enhanced by our proprietary BMS, with 60+ intelligent protections that balance rigorous safety with a smooth user experience. For added redundancy, we’ve included Active Backup Protection via self-control fuses, which instantly disconnect the circuit during abnormalities to prevent permanent damage.

By merging semi-solid technology with LFP chemistry and multi-layered protection, Renogy has successfully pioneered the world’s first smart and portable solid-state battery for mobile energy storage.

Our Commitment to Solid-State Technology

As solid-state technology moves from the lab to the market, Renogy is committed to providing a clear and honest roadmap for our users based on three pillars:

Transparency: We promise to use clear, accurate technical definitions. By avoiding marketing hype and industry jargon, we ensure you have the facts needed to make informed choices.
Targeted Innovation: We are focusing our R&D on demanding off-grid applications, such as RVs, boats, and home backup systems. Our goal is to solve energy storage challenges where reliability and resilience matter most.
True Accessibility: Our goal is to bring advanced battery technology to a wider audience; however, "accessibility" means more than just a lower price tag. We aim to make next-gen tech widely available without sacrificing quality or safety. By optimizing our manufacturing and supply chain, we deliver high-performance, cost-effective solutions that provide lasting value.

Takeaways

When exploring products with emerging solid-state technology, the key takeaway is that there is currently no unified "solid-state" certification standard. Today, given the diverse technical pathways and the incremental nature of its commercialization, "solid-state battery" has become an umbrella term that encompasses a wide range of evolving technologies.

To find reliable power solutions for your needs, we invite you to learn more about Renogy's battery portfolio. Feel free to talk directly to our tech support team, or explore our educational resources on off-grid battery systems.

FAQs

1. Is there an official certification for “solid-state batteries”?

No. There is currently no official, unified global standard or certification that formally defines or "stamps" a product as a solid-state battery.

2. What’s the difference between solid-state and semi-solid-state?

An all-solid-state battery contains zero liquid electrolyte. A semi-solid-state battery is a hybrid that replaces most, but not all, of the liquid with solid materials (such as polymers or ceramics) to improve safety and performance.

3. Are any fully all-solid-state (zero-liquid) large batteries available today?

No. True all-solid-state batteries (ASSBs) are still in the laboratory and pilot production phases. Most major manufacturers do not expect large-scale commercial production until 2026–2030.

4. Does “solid-state” automatically mean safer?

Theoretically, yes, because it removes flammable liquids. However, absolute safety is a "holistic engineering" challenge that still depends on the battery's physical design, its battery management system (BMS), and proper user habits.

5. Why do brands use the term differently?

The term is used broadly because there is no consensus on definitions. Some brands call a battery "solid-state" if the liquid content is below 10wt%, while others believe it must be 0wt%. Additionally, companies are pursuing various material paths (e.g., sulfides vs. oxides).

6. What should I look for when comparing batteries?

Look for technical transparency and established safety credentials (like CE, FCC, and UN38.3). Beyond standard certifications, focus on the integrated safety design: the battery chemistry (e.g., LFP), the BMS, and other features or technologies that match your needs.