Batteries and Energy Storage

­Batteries are a hot topic. Prior to the pandemic, I counted about 355 battery-centric events being held worldwide over a year-long period – almost one a day. This comes as no surprise since the global battery market was valued at USD 108.4 billion in 2019 and is expected to have a compound annual growth rate (CAGR) of 14.1% from 2020 to 2027.

Most of this growth is due to the rise in automotive battery applications. But, overall, energy storage devices are in high demand. The most notable are batteries and supercapacitors. They also include such esoteric devices as flywheel motors that are designed to create ride-through power until generators can come online as an alternative to UPS systems.

Energy storage devices have been used for over one hundred years for powering electrical and electronic equipment. Their power levels range from microwatts in energy harvesting to grid storage systems for alternative energy applications. Actually, battery and supercapacitor technologies are engineering marvels. Regardless of the size of the cell or application, cell chemistry determines the charging profile of voltage and current being applied. The amount of time current/voltage are varied must be considered depending on the temperature of the cell(s).

Significant engineering goes into today’s BMS, or battery management systems, which are designed into applications ranging from phones and PCs to EVs and grid-tied storage. However, energy storage can present challenges. Take grid-tied storage for electric vehicles that require local electrical utilities to produce and transmit (deliver) energy for instantaneous consumption. Since one home’s EV charging station represents an additional typical home requiring 200-amp service, the local utility can’t support an entire neighborhood of drivers plugging in their EVs at the same time. EV batteries with a bidirectional charging system that can return power back to the grid is a good, and probably only, solution. Consequently, using EV batteries to store energy and use it when needed has become the holy grail for utilities.

In addition to the electrification of transportation, battery technology is being spurred by the portable device revolution, as well as the need for UPS systems to power computing, networking and data centers. New applications are coming along daily, including remote weather stations operating in non-daylight hours by using solar-energy harvesting to charge their battery-storage devices. Another is cargo tracking devices that attach to a shipping carton and track valuable cargo during their 5-year battery lifespans.

These new applications require battery chemistries and technologies to keep pace. Although, as I often say, there is no Moore’s Law for batteries, breakthroughs are being made. Recently a French company announced 3D nanotechnology that delivers efficient energy storage and will the manufacturing capacity of its Vertically Aligned Carbon Nanotube (VACNT) materials. Moreover, improvements in BMS systems are on the move. And, not to be forgotten, so are advancements in the load itself. After all, optimizing battery utilization is key to making all these innovations a reality.