Most lithium-ion batteries today use a semi-liquid paste as the electrolyte that transports electrons back and forth between the anode and the cathode. Conceptually, they are similar to the jellyroll your grandmother used to serve as dessert at family events when you were young. The production process is well understood, which allows battery manufacturers to to spit out battery cells by the millions reliably and quickly.
The problem with conventional batteries is that semi-liquid electrolyte can catch fire if it gets too hot. One of the reasons they overheat is dendrites — sharp spikes of lithium metal — can short circuit the battery internally, which leads to overheating. The effect is pretty much the same as sticking a paper clip into both sides of a traditional wall outlet. The paper clip acts like a resistance heater and gets very hot. Trust me when I say you do NOT want to try this at home!
Solid-state batteries use something other than a flammable paste to separate the anode and the cathode. As a result, they can have a higher energy density and a longer service life. They virtually eliminate the formation of dendrites and are usually cheaper to manufacture.
So why are there no solid-state batteries in use today? Because this is new technology. Researchers are constantly looking for new and better solid materials that are flexible enough to get rolled up inside those tiny battery cells, and battery manufacturers need to adjust the production process to accommodate the new technology. But the dawn of the solid state era is almost here, as demonstrated by these two examples.
Samsung SDI Begins Construction Of A Solid-State Battery Factory
According to Electrive, Samsung SDI has begun building a pilot production line for solid-state batteries. The S-line at the company’s research and development center in the city of Suwon will test systems for the production of cathodes and solid electrolytes while trialing the new production processes that will be necessary to manufacture solid state battteries.
Samsung SDI says the 6,500-square-meter S-Line is expected to achieve “market-leading research results and production technologies for solid-state batteries,” but has provided no technical details since it announced 2 years ago that it was testing a solid-state battery cell that would be capable of powering an electric car for 800 kilometers (500 miles) with a lifespan of 1,000 charging cycles.
Yoon-Ho Choi, CEO of Samsung SDI, told the press this week the new S-line would be the “springboard” to make Samsung SDI the world’s No. 1 battery manufacturer through “technological competitiveness, superior quality, and qualitative growth.” Fancy words that may of may not prove to be accurate in the real world.
Sakuu Announces Solid-State Battery
Silicon Valley startup Sakuu announced this week it has successfully created a first generation solid-state lithium metal battery with an energy density of 800 Wh/L. Most lithium-ion batteries in production today have an energy density of between 500 and 700 Wh/L. That’s good news, but what is really exciting is the company says it has developed a new 3D printing manufacturing process that it says will allow low cost production of solid-state batteries with an energy density of 1200 Wh/L by the end of next year.
“The arrival of a safe, sustainable, and high-performance solid state battery, manufactured with a totally novel 3D printing method can solve critical supply chain and safety issues while moving beyond limitations of today’s lithium-ion batteries,” says Robert Bagheri, founder and CEO of Sakuu. “We are on track to develop that ‘holy grail’ solid-state battery by 2023, and this first-generation benchmark is a validating accomplishment on the roadmap to significantly better batteries.”
Sakuu’s first generation non-printed battery is an important step in the race for improved energy storage across broad industry sectors. With the latest benchmark test completed just a few weeks ago, it is closer than ever to production. In addition to its 800 Wh/L performance, it retains 97% of its energy density after 200 cycles while remaining dendrite free. It is expected to record 80% retention at 800 cycles once testing is completed.
The company’s second generation solid-state battery will be 100% 3D-printed with sample cell deliveries beginning in early 2023. Once approved for production, it will offer rapid manufacturing of batteries in high volumes at low cost. “We are creating a line of safe, customizable, low cost and high performance batteries, and manufacturing them in a completely transformative and sustainable manner to satisfy large scale global demand,” says Bagheri.
Sakuu says its groundbreaking 3D-printed solid-state battery cells deliver best-in-class performance and safety in a recyclable format. Its proprietary solid-state electrolyte and porous anode technology provide superior energy densities for maximum range and faster charge times. It believes its printing platform invites manufacturing innovation in a host of other sectors, including aerospace and automotive, consumer electronics, IoT, and medicine.
The promise of low cost, high energy, non-flammable batteries is exciting but there’s many a slip twixt the cup and the lip, my old Irish grandmother liked to say. Today, lithium-iron batteries are all the rage, particularly since they need no nickel, which has risen in price by 5 times in the past year. Tesla thinks it has the future of batteries by the tail with its new 4680 battery cells that are 5 times bigger than standard cells and promise higher energy density at lower cost. But those wonders of innovation don’t use lithium-iron chemistry, which makes one wonder whether Tesla missed the boat somewhat along the way in its battery development process.
The point is this — the internal combustion engines that power most of the world’s vehicles today have been constantly improved for more than a century. Older readers may remember a time when a 1-year/12,000-mile warranty was the standard in the industry and any car with more than 100,000 miles on the odometer was a candidate for the crusher.
Large scale production of batteries for electric cars is only a little over a decade old. There are amazing breakthroughs waiting just around the bend that will transform EVs the way dual overhead cams and electronic ignition systems transformed gasoline engines. We only wish the future would get here sooner. This tired old Earth could sure use a break from the daily onslaught of carbon dioxide from burning fossil fuels.