In the energy sector, lithium-ion batteries are having a moment. Not only are they powering the hottest electric cars like those from Tesla, but they’re also increasingly the tech of choice for companies building battery banks for the power grid.
But despite all the attention around lithium-ion batteries, a handful of entrepreneurs and researchers are focused on their humble century-old cousin: the lead-acid battery.
The last time you thought about a lead acid battery was probably when you absent-mindedly left your car lights on and returned to find a car that wouldn’t start. Indeed, these batteries have limitations. But they’re widely used, not only in cars, but also in wheelchairs, golf carts, and forklifts. They’re also some of the first batteries to be used take buildings off of the grid, and to store energy from solar panels.
The reason they’re still so popular? They’re cheap and they work.
But researchers think they can give lead acid batteries an even bigger role through innovation. If successful, the batteries could be a contender in the growing electric vehicle market and to provide energy storage for the power grid.
The market to use batteries to store energy — from solar panels for when the sun goes down, to better manage electricity flowing through the power grid, and to take buildings off of the grid entirely — is set to explode over the next several years. U.S. energy storage capacity is expected to grow from a small 62 megawatts in 2014 to 220 megawatts by the end of this year, according to GTM Research. That amount of storage would need hundreds of thousands of battery packs. By 2019, capacity is expected to almost quadruple and reach 848 megawatts.
Much of this energy storage boom will come from low cost lithium-ion batteries, many manufactured in huge factories in Asia. But the market is big enough and diverse enough that there could be room for some new emerging technologies. Different kinds of batteries may be better for a particular use. For example, one battery could be great for supplying a six hour-long block of sustained low energy. But another battery could be perfect for a short burst of high power to move a car.
This week, at a small booth at the back of a sprawling solar industry conference in San Francisco this week, stands an entrepreneur who’s been working on a promising next-generation lead acid battery. Christiaan Beekhuis, the CEO and co-founder of startup Gridtential, shows me an early prototype of the company’s “silicon joule” lead acid battery sitting on the exhibition table.
The battery uses important sections made of silicon, instead of the standard lead grids that most lead acid batteries use. Because of this innovation, Beekhuis says his batteries have a higher energy density (can store more energy for their size) and can last far longer than typical lead acid batteries. But producing such batteries could still be cheaper than most of the standard lithium-ion batteries out there.
The company also plans to make its batteries with equipment that commonly churns out computer chips, hard-disk drives and conventional lead acid batteries. That means that Gridtential — or a company that licenses the technology — could buy or use off-the-shelf factory gear to make the batteries.
Gridtential’s battery won’t be commercially available for a couple years, Beekhuis says. But the company has already sent its sample batteries to the big lead acid battery makers, and has used grants from the California Energy Commission and the Department of Energy’s battery lab for research and testing.
Gridtential has raised at least $1 million from The Roda Group, an investor in Berkeley, Calif. that backed Solazyme, which makes fuel from algae, and Internet firm Ask.com. Two former Applied Materials executives, Peter Borden and Michele Klein, founded Gridtential in 2010. Beekhuis, who joined in 2011 to help commercialize the technology, previously founded solar software company Fat Spaniel.
Gridtential isn’t the only startup focused on improving the workhorse lead acid battery. At the solar conference this week, a Michigan-based startup, Energy Power Systems, showed off its next-gen lead acid battery.
That battery — which the company calls the “planar layered matrix,” or PLM, battery — is also supposed to last longer and have higher charge and discharge power than traditional lead acid batteries. At the same time, it’s also intended to be lower cost than standard lithium-ion batteries.
Energy Power Systems plans to start making the PLM battery, which uses both material and design innovations, next year, and has already shipped battery samples to potential customers. The company was founded in 2011 and backed early on by Townsend Ventures.
While the market for batteries for the power grid, buildings and cars is just getting started, building battery startups is always hard. Years ago, one startup, Firefly Energy, tried to develop its own lead acid batteries after being spun out of construction and mining equipment maker Caterpillar, with funding from Khosla Ventures and the Quercus Trust. A few years later the company shut down.
Lead acid battery startups also face additional risk because of steadily declining costs of competing lithium-ion batteries. Many in the battery sector think lithium-ion batteries will drop in cost similar to how solar panels have in recent years. If so, building businesses off of low-cost, commodity lithium-ion batteries would likely be a better bet than trying to push a new kind of battery technology.