I recently finished The Powerhouse by Steve Levine, which tells the tale of the lithium ion battery and its evolving application to electric cars. What I was somewhat shocked to learn was that although lithium ion technology has existed for decades, the lithium ion batteries that are going into the Teslas and Volts was developed in my lifetime, and for the newer generation models, within the last five years. (I had a similar reaction when I learned that the Internet was developed just a couple years before I was born, #millennial.)
What also occurred to me is that we’re a long ways off from creating the ultimate battery. In much the same way engines have continually improved over the last 100 years, so too will a better battery come to fruition every couple years.
Having more than a passing interest in batteries yet no technical background to speak of, it seems to me that there are a couple standout issues with the current lithium ion batteries that will keep scientists scratching their heads to fix: recharge time, voltage fade, and capacity.
None of these are easy things to fix (apparently), and it seems that the current trajectory is incremental improvements on the existing lithium ion technology – a few more cycles before voltage starts to fade, a little more capacity, a little faster recharge time. Sound familiar? It’s the same place combustion engines are at – a little more of this, a little better that. But engines have had the luxury to be refined and perfected over more than ten decades. Lithium ion and car batteries in general are still in their first decade.
If we’re hitting this incremental-only ceiling this early in the game, it begs the question if we’re looking in the right places for the next breakthrough in battery technology. And if I were the person in charge of setting the course towards the next battery innovation, I’d look for types of batteries that solve the issues that lithium ion seems to be stuck with.
My first stop would be to flow cell batteries – essentially batteries that are recharged by draining the spent liquid and refilling it with new liquid. To the consumer, essentially the same time and process of refilling a combustion engine. Oh and they don’t degrade over time. There are several types of flow cell batteries, but the only one that gets talked about is the hydrogen fuel cell, which has its own issues.
What looks most promising from my non-technical end of the table is the vanadium redox flow cell battery. Like lithium ion, the modern form of the battery was discovered decades ago, but has not really been improved upon since. The issue with these batteries currently is that you’d need a whole bunch of electrolyte to produce enough energy to power the car. So much so that it would be impractical to fit into a car. But there is progress on this end, though slow due to so little interest. The Pacific Northwest National Laboratory has created the closest thing to a plausible flow cell battery, but at the moment they don’t talk about it having automotive applications.
In addition, organic flow cell batteries are emerging as potentially the safest and most sustainable type of flow cell battery. This stuff has only been thought up in the last seven years. The advantage over inorganic redox batteries is a huge reduction in cost and more environmentally-friendly materials. Again the PNNL is about the only ones working on this, though the California-based ARPA-E has also looked into it, again from stationary energy storage perspectives.
While I’m not an expert in battery chemistry, it seems that people are so enamored with lithium ion that we haven’t given credence to other battery technologies that may be able to solve a lot of the pain points that exist with lithium ion. Flow cell and organic flow cells are just a couple ideas, and may absolutely not be feasible, but I think it’d behoove the entire energy and electric vehicle industries if we didn’t tell the current batteries they’re great just the way they are – talk about a recipe for parental disaster.