Our Perspective: We need to do better. Time for EV battery management systems to deliver advanced warnings on the safety of lithium-ion batteries.
The NHTSA recently opened an investigation into LG Energy Solution's high-voltage electric-vehicle batteries after their internal failures in several vehicle models led to fire risks and recalls.
What is it going to take to avoid another round of recalls and make EV batteries safer?
The first lithium-ion battery was developed roughly 40 years ago and today we are still learning how to manage this rechargeable battery technology. A key problem is that our understanding of this technology along with standards and regulations have fallen behind the market acceptance level. Many are all in on electric cars and trucks and demand for the latest and greatest EV or energy storage solution is high.
Lithium is active and unstable element and can find its way to creating havoc depending upon its condition. Universities, national labs and companies large and small have been actively working to improve lithium-ion batteries and are spending a lot of time and money to do so. Yet, we are still learning decades later how to develop better materials for anode and cathode, solid state electrolyte vs liquid and better thermal and battery management solutions.
The lithium-ion battery market is strong and lucrative. As a result, researchers, scientists and engineers are often pressured to release new products to the market as soon as possible. At the same time product development basics are being overlooked to meet time-to-market goals. Supply chain challenges have also caused products to race out the door as fast as possible with limited insight and data on what might happen years down the road.
With all the hype in the EV market, one element we cannot and should not afford to overlook is safety. Safety for customers, our communities and the environment. One potential fire, one potential incident can damage a company’s brand while the ensuing costs will significantly overwhelm material or manufacturing savings. The environmental damage from EV battery fires is deleterious.
As EV battery recalls continue to happen much of the hype and revenue growth in the market may be tempered by consumer concerns and doubts with regard to safety.
All of us in the battery industry from material and cell suppliers, EV OEMs, battery management system technology providers need to do better and utilize all of the available technologies and failure mode effect analyses to ensure that batteries will perform safely today, many years from today and in all of the types of second life applications we will use them for.
Battery management systems developed for lead-acid batteries (batteries used for 100 years before lithium-ion) are not sufficient for existing battery technologies. For example, thermal runaway events with lithium-ion batteries happen much faster with much more heat and energy density. This means that existing battery management systems utilizing voltage, current and (slow) temperature sensors need to be improved.
Did you know that most EV battery management systems only estimate their state of charge, state of health and overall performance?
We need to detect thermal runaways faster, understand what is going inside the battery at the molecular level and in real-time, develop solutions on cell vs battery pack or module level and be able to compare battery data from the day it was manufactured to the day it is recycled.
Solutions are under development and one early success has been in using ultrasound to provide real-time battery management and intelligence. Ultrasound enables battery issues and potential failures to be detected on molecular level significantly faster than traditional battery management systems. Ultrasound technology can be deployed for battery cell manufacturing quality control, integrated in cars or renewable energy storage solutions or used to determine which batteries can be safely repurposed for second-life applications.
As an industry we need to come together and agree that safety is priority number one, over any other metric businesses are using today.
Srdjan Mutabdzija Head of Product Development, ESS/EV