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New lithium metal battery doubles energy capacity! Has China beaten US to it again?

Dave Borlace cuts through the hype cycle surrounding next-generation energy storage by confronting a paradox: the battery chemistry that promises to double our range is also the one most likely to catch fire. While the tech world fixates on the headline-grabbing energy density figures from Chinese labs, Borlace offers a rare, grounded skepticism that forces us to weigh the allure of lighter, longer-lasting batteries against the brutal physics of dendrite formation and chemical instability.

The Allure and the Peril

Borlace begins by dismantling the romanticized view of battery innovation. He acknowledges the theoretical upside of replacing the standard graphite anode with solid lithium metal. "A solid lithium metal anode does away with the limitations of the metaphorical graphite bookshelf altogether because the entire block is an active material rather than just some small gaps in between atoms." This shift could theoretically yield ten times the charge per gram, a staggering leap that would revolutionize electric vehicles and aviation.

New lithium metal battery doubles energy capacity! Has China beaten US to it again?

However, Borlace is quick to pivot from the dream to the nightmare. The very reactivity that makes lithium so powerful also makes it treacherous. He explains that without the stabilizing structure of graphite, lithium tends to "clump together and grow into the sharp treelike spikes that many of you will recognize as the dreaded dendrites." These spikes can pierce the internal membrane, causing short circuits and thermal runaway. Furthermore, the element's reactivity creates a crust on the anode surface that "prevents the flow of ions and seriously shortens the battery's life." This dual threat of physical puncture and chemical degradation is why, for years, the industry has treated lithium metal as a "mad idea fraught with difficulty and dangers."

The Chinese Breakthrough

The narrative shifts when Borlace examines recent work from Tanzing University (likely referring to Tsinghua University) and the massive battery manufacturer CATL. The researchers are not trying to force the lithium ions into a rigid, ordered state but are instead embracing chaos. Borlace describes their novel approach: "Instead of trying to force lithium ions into either a solvent dominated or annion dominated structure, the team wanted to create an electrolyte that enabled those ions to exist in a more chaotic, disordered environment that could potentially represent the best of both worlds."

This "deoized electrolyte" strategy was identified through a massive computational sweep involving hundreds of solvents and salts, a task Borlace notes required artificial intelligence to navigate the sheer number of combinations. The result was a formula that allowed ions to move quickly without building up the harmful crust. The data is undeniably impressive: "A 5.5 amp pouch cell achieved 604 W hours per kilogram. And a 5.2 amp configuration with an ultra lean electrolyte using very little liquid managed 618 W hours per kilogram." These figures dwarf current lithium-ion capabilities, suggesting that the energy density ceiling is indeed higher than previously thought.

The best we can hope for here is to mitigate safety risks via improved electrolytes, maybe solid state configurations, flame retardant additives, and strong pack level engineering.

The Reality Check

Despite the dazzling numbers, Borlace refuses to let the excitement override the engineering reality. The most damning evidence comes from the battery's lifespan. While the energy density is high, the durability is not yet there. "The first lab cell went down to 517 W hours per kilogram after 100 cycles. And the ultra lean version only remained stable for about 90 cycles." When compared to the 1,000 to 1,500 cycles expected from a typical Tesla battery, the gap is significant. Critics might note that for stationary storage or grid applications, this lifespan is a non-starter, regardless of the weight savings.

Safety remains the other elephant in the room. Even with improved electrolytes, the fundamental nature of lithium metal means it will react violently if the cell is breached. Borlace contrasts this with lithium iron phosphate (LFP) batteries, noting that "you can drive a nail straight through the middle of an LFP cell and nothing happens." He argues that while the new technology might be viable for premium long-range EVs or drones where weight is paramount, it is unlikely to replace safer chemistries for mass-market commuter cars anytime soon. The industry giants like CATL are pursuing this path, but Borlace warns that their claims of "over 500 W hours per kilogram" leave "quite a bit of linguistic wiggle room" regarding the actual commercial viability.

Bottom Line

Borlace's strongest contribution is his refusal to treat a laboratory prototype as a finished product, grounding the breathless hype of "doubling energy capacity" in the hard metrics of cycle life and safety. The piece's greatest vulnerability is its inherent pessimism; while the cycle count is low, rapid iteration in battery chemistry often yields exponential improvements in a short time, meaning today's 90-cycle limit could be tomorrow's 500. Readers should watch for the next generation of these deoized electrolytes, as the gap between lab success and commercial reality may close faster than the author anticipates.

Sources

New lithium metal battery doubles energy capacity! Has China beaten US to it again?

by Dave Borlace · Just Have a Think · Watch video

Long-term viewers of this channel will know that when I'm not banging on about how bad the climate emergency is, I can often be found talking about potentially exciting new battery technologies. I do that not because I suffer from any delusion that battery energy storage is the solution to our somewhat existential predicament, but because I recognize that it will at least play a key role in the renewable energy future that the world will have to reach as soon as possible if we want to have any chance at all of maintaining the comforts and conveniences of our modern way of life. I've made dozens of videos over the years covering the various combinations of chemistries and materials under development. I even made a full comparison video last year with a breakdown of the pros and cons of all the main contenders.

One option I haven't looked at in any great detail though is the concept of using a solid lithium metal anode to replace the graphite anode that's typically used in the vast majority of existing lithium ion batteries. And that's because for a whole range of reasons that I'll come to later in the video, it looks like a mad idea fraught with difficulty and dangers that at least on the face of it ought to make it a complete non-starter. And yet chemists have been kept super busy in their laboratories over the last decade or so, relentlessly striving to iron out the shortcomings of lithium metal battery or LMB technology. And now, even the world's largest battery maker, CL, has thrown its hat into the ring, recently announcing some sort of breakthrough in lithium metal technology.

At almost exactly the same time as researchers from Tanzing University at the other end of China, published their own research outlining another apparently groundbreaking technique that they reckon can potentially double the energy density of existing lithium-ion batteries. So, go on then. I'll bite. Hello and welcome to Just Have a Think.

So, why am I coming over all cynical and skeptical about lithium metal batteries? Then, while I can see the attraction, don't get me wrong, the graphite anode in a typical existing lithium-ion battery is essentially multiple layers of carbon with spaces in between that lithium ions can be squeezed into as the battery charges. That's the intercolation thing that I've talked about in previous ...