When lithium-ion battery technology replaced nickel cadmium (NiCd) and nickel metal hydride (NiMh), we really felt like the power tool industry had arrived. In reality, we did. Many cordless tools finally had the ability to replace corded models with plenty of power and all-day runtime. All that might change again with the successful development of a new solid-state battery.
New solid-state battery technology (already used in remote-controlled cars and electronics) promises longer life cycles. It also has the potential to charge and discharge more rapidly. Finally, solid state can be developed so that it doesn’t rapidly combust. Perhaps most importantly, it can be manufactured less expensively. Unfortunately, in order for solid-state batteries to supplant lithium-ion, it needs to hit the high current levels required for power tools.
How Does Solid-State Battery Technology Work?
Batteries discharge energy and in return charge by moving ions between the negative and positive side of the battery. The direction of the ion shift determines whether the battery is giving out energy or taking it in. From there, we meet John Goodenough (yes, that’s his real name). Never heard of him?
He’s one of the co-inventors of the lithium-ion battery. Even though this technology only took over the power tool industry a few years back, he helped invent the technology 37 years ago. At the age of 94, Dr. Goodenough is doing much more than good enough by creating a successful glass electrolyte solid-state battery.
Instead of using a liquid electrolyte to transport ions between the negative and positive sides of the battery, the solid-state form uses sodium instead of lithium. Both are alkali metals effective for transporting those ions. Considering how much of the Earth’s surface is covered by seawater, sodium is a widely available—and cheap—alternative. If it can be used in place of lithium, prices go down even if the performance is identical. But of course, it’s not.
What Other Benefits Are There?
When I say that a solid-state battery can charge quickly, I mean ridiculously fast. Lithium-ion batteries that currently take hours to charge will take mere minutes. It’s much denser than lithium-ion, storing some three times the amount of energy in the same space. You also end up with the battery that still has high conductivity down to four degrees below zero (or -20 degrees Celsius).
Let’s not overlook the significance of the stability of a solid-state battery. One of the biggest dangers—as Samsung has famously proven with its S7 smartphone—is battery combustion. The fact that the new technology eliminates this risk means manufacturers can create much more aggressive tools with lightning fast chargers. They can also ship them via air freight—a huge boon for batteries given current restrictions.
Uses for a Solid-State Battery
There are obvious products that can benefit from solid-state technology. Nearly every adult (and seemingly child) in the United States and other developed countries now carry a smartphone. Imagine a battery that will power your phone for days instead of having to recharge after a busy morning—all without increasing the size.
One of the most power-hungry product groups getting excited about this breakthrough is the electric car side of the auto industry. Greater range, better acceleration, and lower prices have the potential to make electric cars available to a greater number of buyers.
But what we are really excited about is power tools. We’re just breaking into tool classes like belt sanders and SDS-Max rotary hammers. What other tools might be unlocked for the cordless realm: Power cutters, augers, generators?
And let’s not forget about outdoor power equipment. Ryobi just launched a $2,500 battery-powered riding lawnmower that uses four lead-acid batteries. It’s able to run for two hours and cut two acres on one charge. Imagine being able to run for six hours!
The Bottom Line
More power, longer runtime, faster charging, complete stability, and lower pricing make it seem like the solid-state battery is the perfect solution to power virtually everything that uses batteries. Could it replace lithium-ion technology overnight? We’ll have to see. With the information that’s available so far, however, there’s not really an obvious downside to this new breakthrough.
I’ll go on record as saying that if it sounds too good to be true, it probably is. However, until we start seeing products in the hands of real-world consumers, we’ll have to rely on lab tests and scientific studies to determine what those limitations will be.
It took the better part of 30 years for lithium-ion technology to find its way into mainstream cordless tools. One of the big questions is how long solid-state will take to move in. Another area of concern for most current cordless tool users is whether or not a new solid-state battery pack will run a tool designed for a lithium-ion pack. After all, NiCd and Lithium-ion aren’t cross-compatible. Our guess, however, is that since the transition to smarter packs and tools has already taken place, the shift will occur more readily.
Let’s hope it doesn’t take nearly that long for solid-state battery packs show up. When they do, it’s a good bet we’ll think of lithium-ion batteries the way we do NiCd right now and wonder how we ever built a house without them.