George in terre Haute and battery tricked charge

I am not even close to high-teck as friend george. I am of the type if small hammer does not work, get the BFH. Batteries which came with harbor freight tools for interment use need something, but what for guys like me. I bought timer at wal-mart ( I know George , should have went to Menards) set timer for 45 minuets each 12 hours. Plugged in receptical strip which allows 6 different chargers. Seems to work for me.

Bill, my trickle charging idea to keep cordless batteries up in cold pole barn was a BUST. There is no substitute for having a warm place to store and charge batteries. In my quest to make a trickle charger, I discovered that all Nickle based batteries, NI-Cd and my favorite Ni-Mh, will self discharge sitting on a warm shelf to the tune of up to 20% the first 24 hrs. After that about 1% per in day up to a certain point. That may explain why if you don't use your tools often your battery is dead.

Ni-Mh battery don't have a memory and don't have to be discharged and cared for like Ni-Cd. I think I read where you could top them off Ni-Mh like thousands of times no problem. Not recommended for your battery.

I also learned from experience, if you have two 12v batteries in series, one battery is weak, and you fully discharge them, the weak battery will take on an opposite polarity and it's junk. The same is true when discharging cordless batteries. If one cell is sick, fully discharging the battery, like is recommend for Ni-Cd, will damage the cell. So you are left with taking battery apart and shorting out each cell. No way, no how, I'm not going to do that.

Here is your deli-ma. Changing over to a different battery will require a special Charger. In my situation, I purchased two Li-ion batteries, only 2000 mahr and got the required charger for around $200 back in 2009. Shortly after the one Li-ion battery dies. Dewalt designed this charger for all 3 types of batteries. The upside to Li-ions is they don't self discharge, however, like all cordless batteries, they will not work in cold temps either. So I carry my only Li-ion battery and a few other Ni-Mh batteries on the floor of truck along with a truck charger. When I driving, batteries warm up, so I can have a fresh battery to work with. When the Ni-Mh batteries are warmed, I'll put them in charger, usually is about 10 minutes or less to topped off.

So what do I do if I were you? Use the BFH on your cheap cordless tools and get a better brand of tools that you can buy different batteries for. My guess is you will find someone to rebuild your Ni-Cd batteries. If your timer works for you great. You may want to take battery apart, make sure no cell has reversed polarity. Short out each cell one at a time. Doing that may end up damaging your charger. So good luck. When all else fails, use the hammer. geo