BATTERY EVOLUTION
Future of Cell Chemistry?
Solid-State Batteries: In these batteries, liquid or gel electrolytes are replaced with solids. This technology could deliver higher energy density, faster charging capabilities, increased safety, and greater flexibility in form factor. Solid-state chemistry has been discussed for years. Samsung SDI is reportedly ready to mass produce solid-state batteries beginning in 2027.
Kress is using pouch cells in its CyberPack batteries.
“ It is known for better safety and is more energy dense than NMC,” said Conrad.“ I’ d prefer to go there next but I don’ t know if we will. Going to a lithium iron phosphate battery would almost be like going backwards at this point.”
Sodium-Ion Batteries: The abundance and global distribution of sodium make a sodium-ion battery appealing. This reduces supply chain disruptions and lowers material costs. While their energy density is currently lower than lithium-ion, their cost-effectiveness and improved supply chain resilience make them an attractive alternative, especially for less energy-intensive or cost-sensitive OPE applications.
Size
Most tool battery packs are made up of cylindrical battery cells. There are two common sizes: the 18650 cell( 18mm diameter, 65mm length) and the 21700( 21mm, 70mm length). A battery pack for a handheld string trimmer might contain 8 or 12 battery cylinders. A Tesla Model 3 contains about 4,000. And they could v ery well be the same cylinders. The Tesla CyberTruck uses primarily 4680 size battery cells.
The 18650 size is common and older. Tesla teamed with Panasonic to create the 21700 cell in 2017. The increased volume improved energy density. For power equipment makers, battery packs changed shape to accommodate the larger 21700s, but it increased efficiency too. The newer cells can also be more cost-effective to assemble due to fewer components and fewer spot welds required during manufacturing.
“ Our cyber pack batteries are pouch designs,” said Zimmerman from Kress.“ It allows us the best design to utilize the chemistry versus rolling that up into a cylindrical design.”
Stihl uses pouch technology in its top-of-the-line AP 500S battery.“ We’ re able to pack more energy content into that battery than any other,” said Beblowski.“ And we’ re able to extract a lot of power out of it, extremely quickly, and all of that is Stihl proprietary product.”
“ Pouch cells are well suited for delivering high power in a compact form factor but are less ideal for applications requiring extended runtime, frequent charging cycles, and effective heat dissipation,” said Zafir Farooque, group product manager at Milwaukee Tool.
Another advancement in battery cylinders is the tabless design. A tabless cell increases the points of contact, basically, for the cell’ s electrodes, and helps reduce resistance. Instead of using single points of contact for both the anode and cathode, a tabless cell is better able to use all the electrode material. That means increased storage, faster charging and other benefits.
Tabless is another Tesla creation, announced on Battery Day in 2020. It also brought out the 4680 cell size at the time.
“ The tabless design will continue to catch on,” said Zimmerman from Kress which uses tabless cells.“ The tabless design allows the cell to be smaller, more compact. It allows the cell to stay cooler longer, so you can charge it faster, have more life cycles out of it, and get a little bit more power out of it. We’ ve adopted tabless into batteries to operate for power tools and for outdoor power equipment. So if you compare a tabless battery to a typical cylinder battery cell, it’ s generally half the size, half the weight.”
Shape
If you’ re thinking about your phone right now and wondering about its battery, it’ s a pouch cell, using thin layers of metal and chemicals encased in a rectangular tinfoil-like pouch. Some tool makers use these pouch cells too.
18 OPE + September 2025 www. OPE-Plus. com