Batteries Power Up: Perception vs Reality

Perception: Batteries are boring. We notice them only when they’re dead. Reality: We tend to think about batteries as unreliable nuisances, depending on them only when a power outlet isn’t available or when we don’t have to travel very far in our electric cars.

But in 2017, the world’s largest lithiumion (Li-ion) battery, developed by Tesla, short-circuited that image by providing lightning-fast backup power to stabilize the power grid in South Australia, where storms and heat waves have been wreaking havoc since a major blackout in 2016.

The Tesla battery not only reliably fills the gaps in power generation, it does so faster than coal-fired power plants that normally come to the rescue when the grid is overloaded. More importantly, it is the first sign that if battery power and capacity continue to improve, batteries could bring clean, renewable energy to primacy by covering the hours when the sun isn’t shining and the wind stops blowing. Perception: up. The technology can’t keep Reality: The capacity of the market-dominant Li-ion battery has improved 300% since its introduction.

But that was in 1991—eons ago, considering the technology that batteries now power. And when these batteries occasionally burst into flames, it’s hard not to be frustrated by the slow progress. But alternatives are finally coming into view.

Engineers predict that a safer battery, using the less-expensive and less-combustible silicon, will hit the market with a boost in battery capacity of up to 40% in the next two to five years. Meanwhile, an experimental battery that uses a microscopically thin layer of graphene on its electrodes charged up five times faster and had up to 45% more capacity than a regular Li-ion battery (without the fireworks). Other experiments include solidstate batteries, an alternative to most advanced batteries, which use liquid to conduct electricity, and 3D-printed batteries made from copper foam and gold nanowires that can be recharged 200,000 times without losing capacity.

Perception: You have to plug them in to recharge.

Reality: Today’s batteries can’t survive for more than a few days without access to a power outlet to restore their energy (assuming they can be replenished at all).

But a new generation of power cells is asserting power independence in the lab.

For the diminishing portion of the population that still uses a mobile phone for voice calls, sound waves could help keep the phone batteries fresh. If gabbing for power sounds tiring, researchers have discovered ways to harvest energy from all sorts of nonelectrical sources, including radio and TV waves and negative vibes in the form of that annoying colleague who’s always impatiently tapping his fingers on the meeting table. Though the relatively low levels of energy developed through these piezoelectric methods won’t keep the grid up at night, they have excellent potential, combined with solar energy, to power the small Internet of Things sensors that are already beginning to monitor the world around and inside us.