Solid-state batteries have been promising to save electric vehicles for so long that they’re starting to seem less like technology and more like a recurring motivational speech. More range, faster charging, less weight, better safety. Great stuff, assuming one can actually build things without microscopic lithium spikes and causing short circuits.
That annoying little problem is called dendrite formation, and Researchers from MIT and the Technical University of Munich Maybe a better way to control it has been found. As highlighted by our friends InsideEVSThe MIT study focused on grain boundaries inside ceramic solid electrolytes, which are basically microscopic seams where tiny crystalline grains meet. Those seams can impede the movement of lithium ions and create electrical conditions that encourage lithium metal to accumulate.
Once the lithium begins to form into thin filaments, it can eventually punch through the electrolyte and connect the two sides of the battery. This is bad in the same way as drilling into a fuel tank with a cordless drill is bad. The battery may go short, fail, overheat, or become an expensive science experiment that no one wants to see stuck between their knees.
Photo by: Verge Motorcycles
The researchers studied a ceramic material called lithium lanthanum zirconate, commonly shortened as LLZO, and found that electrical imbalance at its grain boundaries was helping to create conditions for the formation of dendrites. By changing the way the material was processed, they reduced those imbalances and allowed lithium ions to move more freely through the electrolyte.
The modified material handled more than 300% critical current density compared to the baseline sample before shorting. This doesn’t mean 300% more range, 300% more battery capacity, or five-minute charging stops after a heroic blast into the sunset. This means that the material tolerated a lot of current before the lithium filaments caused trouble.
For electric cars, this could eventually help unlock faster charging and more energy-dense batteries. But for electric motorcycles and powersports machines, the implications could be even bigger because these vehicles don’t have acres of land available for battery packs.
Photo by: Honda
A car can carry a huge battery under the cabin and use its wheelbase to hide the results. A motorcycle has to fit its batteries inside a frame that still needs suspension, cooling hardware, steering clearance, crash protection and room for a rider who wouldn’t want to sit six feet above the sidewall.
That’s why today’s electric motorcycles often face a choice between useful range and reasonable weight. A more energy-dense solid-state pack could increase range without making the bike bigger, or maintain current range while reducing meaningful weight. The second option may be more transformative. A lighter battery can improve steering, braking, suspension response, low speed control, and the general experience of pushing something backward down a driveway.
The same logic applies to electric dirt bikes, ATVs, side-by-sides, snowmobiles, and personal watercraft. Off-road machines need enough power to remain useful without becoming too heavy. Snowmobiles need battery systems that can survive the brutal cold. Personal watercraft demand high power for long periods when operating inside a wet, tightly packed hull.
Photo by: Can-Am
The problem is that the laboratory electrolyte is not a finished powersport battery. Ceramic materials still need to survive years of vibrations, potholes, bounces, crashes, chassis flex, pressure washing, cold temperatures and repeated charging. Battery manufacturers also need to produce materials consistently and cheaply so that future electric dirt bikes won’t cost as much as a lightly used pickup truck.
Still, this work matters because it attacks one of the most stubborn failure points of solid-state battery technology at the microscopic level. If manufacturers can better control grain boundaries, they may be able to make batteries that handle more current, resist internal shorts and make lithium-metal anodes more practical. This will not allow electric motorcycles to travel long distances. This can ultimately prevent the battery from determining the overall size, weight, shape, and personality of the machine.
