By David Lee
Batteries are important to the average consumer’s daily routine. From your electric toothbrush to the TV remote, lithium-ion batteries make our lives easier. So when a battery’s life runs out, it’s no surprise that some frustration kicks in. This limited energy storage capacity is why the industry continues its research to advance and commercialize a longer-lasting battery. But is the push to get there first impacting the safety of those who use this technology on a daily basis?
When it comes to the journey of advancing batteries, the energy storage industry’s primary focus is on advancing lithium-ion batteries. These technologies possess an overwhelming advantage over the other types of batteries on the market. In comparison to what’s commercially available right now, Li-ion batteries have a substantially higher energy storage density that facilitates a smaller footprint, which minimizes the weight and size of these devices — and because of its low self-discharge property, the electrical energy stored lasts longer.
Today, the battery industry’s approach to making the lithium-ion battery safer has generally been effective. But news of the many different battery fire incidents, such as the Samsung Note 7, have plagued developers of energy storage technologies.
Looking back at the situation, consumers experienced a devastating result from the company’s decision to increase the energy storage capacity without a sufficient safety provision.
If not developed correctly, a lithium-ion battery’s high energy storage density can pose a greater risk of battery fire. After 35 reported incidents of overheating smartphones worldwide, the company decided to recall all Galaxy Note 7 devices, which subsequently led to every U.S. carrier halting sales of the Samsung Galaxy Note 7.
Further complicating the efforts to make batteries safer is an overwhelming demand for higher energy density lithium-ion batteries to meet the market demands for cost-efficient electric vehicles (EVs), smart homes and other next-generation technologies.
Now, many industries are depending on the advancement of these battery technologies to satisfy the need for higher density. Questions often asked by the unassuming general public include:
- Why can’t we use our iPhones for several days straight without having to recharge them after eight to 10 hours?
- Wouldn’t it be nice to drive our EVs from Los Angeles to San Francisco without worrying about locating a charging station along the way?
- When will we be able to purchase electric vehicles that cost about the same as conventional vehicles — or even less?
The answers to these questions all come down to higher battery capacity, faster charging ability, and lower cost of lithium-ion batteries.
Over the years, the battery industry identified the common causes of a lithium-ion battery fire as electrical shorts, impact and mechanical deformation, and other technical issues. These issues are identified through cell- and system-level failure analysis, and by studying the causes of the thermal runaway at the material, cell, and system level.
To date, the battery industry has focused on detecting thermal runaway and managing the cell temperature with the use of some form of battery management system (BMS), which often relies on embedded sensors in the battery cell or module to collected data and perform operational diagnostics. Research activities also include using mathematical modeling and computational analysis of such data, as well as solid-state electrolytes that are far less likely to blow up or vaporize than organic solvents.
The causes and mechanics of battery fires are well understood by the battery industry, but there is no single silver bullet that can completely mitigate the problem. The general consensus of the scientific and engineering communities is that smart and diligent safety design practices will be the most important factors to prevent future mishaps.
Scientists and engineers strongly agree that improvement in material technology within battery chemistry, as well as consistent safety design practices (packaging, system design, detection and isolation of fire to stop propagation, etc.), will help drastically reduce the occurrences of battery fires.
Research at many different levels (material, electrodes, cells, batteries, manufacturing processes, etc.) is underway as we continue the search for improving energy density, increasing the charging speed, and lowering the overall cost.
At the material level, silicon (Si) is one of the most promising anode materials being considered for next-generation, high-energy and high-power lithium-ion batteries. However, Si anodes suffer from large capacity fading and tremendous volume changes during lithium-ion charge/discharge cycling. These strains are due to the huge volume changes that actually pulverize the Si material and eventually lead to electrode shattering and delamination, which adversely affect the battery performance and cycle life.
It is obviously not easy to solve all of these problems at once, but I believe it is possible to significantly improve battery capacity and lower cost using innovative new technologies, such as BioSolar’s unique Si material technology.
I’d like to end this blog, taking a cue from a 1966 song by the Beach Boys called “Wouldn’t It Be Nice.” Wouldn’t it be nice if we could take a five-hour trip in an electric car without having to recharge it, or maybe not have to recharge our iPhones every single day? That’s the kind of world where we belong.
Image credit: Pexels
David Lee is CEO at BioSolar, a company developing breakthrough technology to double the storage capacity, lower the cost and extend the life of lithium-ion batteries.