31Oct 2018

The break I took from writing is over. I hope many of the readers took the time to read, re-read and digest the insight I shared in my earlier blogs. 

My return theme is around battery safety.  Since 2016, when the Samsung Note 7 became headline news, there have been countless reports of battery safety problems, several of them with catastrophic outcomes. As ominous as they are, these events are covered on the second page, not the first page. But that should not offer any of us any peace of mind….as the old saying goes “where there is smoke, there is fire.”

The Washington Post and other media outlets reported today that Lime, the company that is deploying thousands of electric scooters on US streets, has recalled some of its scooters because of the risk of fire in their batteries. The company, in a statement, admitted that a “manufacturing defect” may result in the “battery smoldering.” Indeed, on August 27, a Lime scooter caused a fire at the company’s Lake Tahoe facility.

Lime said that the problem is rare, with only 0.01 percent of its fleet of scooters recalled. The fact is that 0.01 percent is not a small number when it comes to battery safety. For the Samsung Note 7, that figure was less than half….yet, it was not pretty. 

The Lime scooter story is not the only one that highlights the rising safety risks of lithium-ion batteries. On June 22 of this year, Nazrin Hassan, CEO of Malaysian tech company Cradle Fund died at the hands of his smartphone which allegedly exploded in his bedroom as he slept nearby. Hassan’s brother-in-law said that he had two smartphones, a Blackberry and a Huawei. They did not know which one exploded. 

These are just two recent examples where battery safety caused or risked causing a tragic and catastrophic outcome. A web search for “lithium-ion battery fire” returns over 21 million entries. So if battery fire risks are so real and increasingly common, why are we not taking this issue more seriously?

The coming year will witness the deployment of 5G wireless network. It is an amazing new evolution in how we communicate via wireless devices. But 5G will also place a severe burden on the battery. We are already testing new generations of lithium-ion cells with terminal voltage of 4.45 V. To put in perspective, the battery voltage used to be 4.2 V only a few years ago. The increase in battery voltage has erased any safety margin that was built in the older generations of batteries. 

Electric vehicles are growing in numbers. The Tesla model 3 was ranked among the best selling sedans in North America this summer. More auto manufacturers are introducing more electric models on our streets. It is a great evolution towards green transportation. But how will we react to battery fires in vehicles?

Statistically speaking, battery events occur at the rate of about 10 to 100 failures for every one million devices (in technical lingo, 10 to 100 ppm). This may sound like a small numerical figure, but when multiplied with the billions of devices that use batteries, the number of safety problems becomes very troubling.  Yet, there are technologies that can reduce this figure by a factor of 100 (down to parts per billion or even lower). It’s time that the battery safety is taken far more seriously.