Back in 2004, Diane was looking at getting a reciprocating saw. Despite the indications that one simply should get the Milwaukee Sawzall and be done with it, we instead got a kit of Ryobi power tools that included a reciprocating saw. Ryobi is the Home Depot’s own brand of power tools, and occasionally Home Depot marks down kits deeply. In 2004, they had a pretty deep discount on the Ryobi 18V kit that included a reciprocating saw, 10″ chainsaw, circular saw, jigsaw, drill-driver, flashlight, and handheld vacuum. We found the purchase relatively disappointing, though, for one specific reason: the batteries and charger that came with the kit made the tools practically useless.
The Ryobi batteries circa 2004 were of one chemistry type, nickel-cadmium (NiCad). NiCad batteries are rechargeable, sure, but they are prone to a number of defects and do not yield high amp-hour figures. One of the most serious problems with NiCad batteries is a memory effect. If one does not completely discharge a NiCad battery each and every time it is used, it will tend to decrease in maximum charge capacity over time. It is really tough to do this well enough to keep NiCad batteries in top condition, so despite the fact that one can theoretically discharge and recharge a NiCad battery about a thousand times, its useful life tends to be a small fraction of that.
But the proximal problem we had was that the NiCad batteries didn’t have much in the amp-hour capacity department, and Diane would find that she would get perhaps half an hour’s work out of one battery used in the reciprocating saw. The battery would then need about 90 minutes to recharge, which meant that even with the two batteries that came with the kit, she was limited to perhaps a bit over an hour of useful work with the reciprocating saw before she had to simply let the first battery used recharge for another hour or so.
This problem with the power source colored our views of the Ryobi gear quite negatively. This contrasted sharply with our experience with 12V Makita power tools. We got our first Makita cordless drill sometime in the early 1990s, and while it used NiCad batteries as well, we didn’t get left with the feeling that the batteries would leave us high and dry with a lot of work left to be done. Of course, a drill may not have the power requirements of a reciprocating saw, but our impression of the comparison between the two brands was strongly shaped by the poor performance we got out of the Ryobi tools matched with their NiCad batteries and charger.
Recently, we had a task to accomplish. We had a survey done on a parcel of land, and the survey company said something about needing the area where a marker would be placed cleared, and needing line-of-sight to a position where their GPS instruments could be used for a high-precision fix. One corner of the land, though, had some heavy brush, including the invasive Brazilian pepper, that would need to be removed. By experience, we had come to the recognition that the Ryobi chainsaw was generally more efficient at cutting than the reciprocating saw. But the batteries made this only a partial solution because we had a lot more than an hour’s work to be done, and not enough time to be taking hour to hour-and-a-half breaks for every half hour of work.
We had resisted investing more money into the Ryobi toolset thus far, so while we knew that Home Depot had introduced an improved battery system, we had passed on buying into it. We decided to give it a try. We stopped by a Home Depot and bought two of the high-capacity 18V Lithium Ion batteries ($89.95 each) and a matching charger ($27.95). That turned out to make a huge difference in how well the Ryobi power tools performed.
We were able to work pretty much continuously with the Ryobi chainsaw. By the time we had discharged one Lithium Ion battery, the charger managed to have charged the other. The fact that we had to remove the cleared brush as well as cut it probably helped a lot there; I’m not sure that someone doing chainsaw sculpture, as a neighbor of ours in Galveston used to do, would have the same experience. But I’m confident that they would find the newer battery technology a huge improvement over the NiCads, as we have.
While we’re not so happy at having had to invest about $210 plus tax to make the stuff work like it should have to begin with, we are pleased with the performance so far of the Ryobi Lithium Ion batteries with the Ryobi power tools. If you have a Ryobi power tool gathering dust because trying to use it with the NiCad batteries is just too painful to deal with, getting the Lithium Ion batteries does seem to be a possible alternative to buying new tools in a different brand. If you are considering buying new power tools, the Lithium Ion batteries should make Ryobi far more competitive when comparing the different brands head-to-head on performance. Just make sure that if you do buy Ryobi, get the tools packaged with the Lithium Ion battery system. Home Depot still sells NiCad batteries for Ryobi (and apparently rather a lot of them, based on the number I’ve seen carried in stock in the stores), but I’d recommend strongly against trying to get work done while dependent on those.
I may have to disassemble one of the old NiCad battery packs and see what sort of cells are used in it. It might be possible to physically replace the cells with nickel-metal hydride (NiMH) cells. NiMH offers much higher amp-hour capacities than NiCad and reduces the memory effect almost entirely. NiMH does have higher self-discharge rates than Lithium Ion, which may be why Home Depot decided to go with Lithium Ion and not offer NiMH-based batteries in the 18V line. Back to the DIY battery modification, though; if I did upgrade the cells in the 18V shell, would I be able to charge it with the new Ryobi charger? I think the charge profiles for NiCad, NiMH, and Lithium Ion may all be different, and certainly the Ryobi One 18V charger was not designed to handle NiMH. Any advice from battery aficionados out there?