Cordless drill

I bought Ryobi last year, partially because brand new battery packs cost only $20 each (and a lot of other brands cost two or three times that much).

Harbor Freight was selling a �kit� with 18-volt drill, trim saw, flashlight, charger and two batteries for $100. I couldn�t pass that one � and bought two spare batteries at the same time.

No complaints after several months -- and the saw works surprisingly well and is "handy as pockets on a shirt".

The term "memory" refers to a tendancy for NICADs which are repeatedly partly discharged to eventually limit their capacity to however much they've been discharged. Modern NICAD batteries have almost no "memory", and only show that if they're repeatedly charged and discharged to exactly the same level. In a service such as a cordless drill, the chances of you repeatedly discharging the batteries to the same level before every charge is almost nil. Newer technologies such as NiMH do not show memory effects.

"Memory" was a problem at one time with applications such as low-orbit spacecraft, where the batteries would be repeatedly charged and discharged to the same level as the craft went in & out of eclipse. Even with older technolgy batteries, a couple of deep discharge/charge cycles would eliminate any memory effects.

"Solutions" such as freezing the batteries will sometimes work as a short term fix. What's probably happened in your case is that one of the cells has developed a high-impedance internal connection, which limits the total amount of current the batteries can provide.

A fix? As much as I hate to contribute to our disposable mentality, throw the drill away & buy a new one. There are places that'll replace the cells in your existing battery pack, but it'll probably cost you more to have that done than to simply buy a new drill. Last new drill I got was actually cheaper than replacing the batteries in the old one, and it works a lot better.

Keith

Based on my own experience, heat is the biggest culprit. Fast chargers cause over heating. A price you pay for convenience. Improper storage that exposes the battery to high temp. is also a killer. I keep my batteries in a cooler when on my service truck.

Use a slow/low charge rate of approx. 100ma for 12 hours. Discharge the battery from time to time using a resistor that puts about a 500ma load on the battery. Don't over discharge. Nicads have a limited range between full charge and discharge.(1.25vdc to 1.20vdc)

I normally get about 14 months use from a battery pack. I've tried repairing the packs but mixing new cell's with old has not worked very well.

Rechargeable tools of any kind are a last resort. They're neat and handy but just not that dependable for day after day hard use.