The battery industry got a jolt recently when Toyota and Mazda announced a new $1.6 billion U.S. assembly plant partnership that will include cooperation on developing and producing new batteries and new vehicles that use batteries. Toyota aims to develop a vehicle based on a new type of battery, known as a lithium-air battery or solid-state battery, that would reduce charging time to be comparable to the time it takes to fill a gas tank, while increasing range and lowering costs.
Toyota joins an increasingly crowded field of players competing for the thriving battery market. The lithium-ion market alone is expanding at a compound annual growth rate of 16.6 percent, on track to reach a value of $68.97 billion by 2022, Markets and Markets projects. Demand for smartphone and car batteries is driving the growth of this and other segments of the battery market, and is fueling innovation as competitors seek to gain an edge. Here’s a look at three trends in battery innovation that are making batteries charge faster, last longer and run safer.
For both car and smartphone manufacturers, one of the top goals motivating battery innovation is demand for faster charging. Significant investment in this endeavor has yielded a steady series of results. A good example is the Quick Charge technology on Qualcomm’s Snapdragon mobile processors.
Quick Charge technology is based on tackling a limit placed on battery charge time by the ability of batteries to withstand current. Increasing current at a set voltage accelerates charge time, but also exposes battery components to higher power, requiring greater durability. Smartphones are designed with regulator circuits that keep charging within safe levels. Quick Charge increases the amount of current a battery can safely draw at a time, accelerating the charging process. The latest Quick Charge 4.0 upgrade represents a 20 percent improvement on its predecessor’s charging speed, along with a 30 percent improvement in efficiency, while running 5 degrees Celsius cooler. This allows a user to get five hours more battery life from an additional five minutes of charging.
Another major goal of manufacturers is increasing battery longevity. Batteries wear out over time because the process of charging and using the battery moves ions from and to the cathode, gradually wearing it out and reducing charging capacity. Anodes can likewise wear down. Additionally, energy gets dissipated as ions become trapped over time, preventing them from flowing.
Battery manufacturers have been developing a number of methods to overcome these limitations. One approach being pursued by the Korea Advanced Institute of Science and Technology is making battery anodes out of silicon and using molecular “pulleys” to keep the silicon from deteriorating. Anodes are usually made out graphite, but silicon can hold five times more energy. The problem with using silicon is that it expands to four times its size and then cracks, making batteries wear out quickly. The KAIST team found that creating molecular pulleys to restrict silicon expansion enabled batteries to retain 98 percent effectiveness after hundreds of recharging cycles.
Since last year’s launch of the Samsung Galaxy Note 7 was crippled by a manufacturing defect that caused the tablet to catch on fire, safety has become an urgent priority for battery manufacturers. To prevent future incidents, Samsung has been working in partnership with MIT to improve its battery safety testing process in preparation for the launch of the Galaxy Note8. Samsung’s previous testing process had only five steps, but its new process has expanded this to eight steps, adding charge/discharge, volatile organic compound and battery aging tests. Samsung says the new process has significantly improved the safety of its batteries.
Other manufacturers are experimenting with new battery materials to improve safety. Massachusetts startup Ionic Materials is testing solid-state alkaline batteries, which are less prone to combustion than lithium-ion batteries. The company has also developed a solid lithium polymer battery that is resistant to combustion.
These trends not only spell out advancements in the battery market but advancements in all technologies that rely on battery power. What’s more, continued improvement and innovation is this field points to a greener, safer and more efficient world.