to kill or not to kill - Contractor Talk - Professional Construction and Remodeling Forum

Norrrrrrrrrrrrm · 10-31-2007, 07:30 PM

I have heard from from many people tell me many different things when it comes to charging a rechargeable battery. Some say drain till it's ka-put, other say when you first sense power loss revive the little bugger. My question is, who here knows what the real deal is and why?

KillerToiletSpider · 10-31-2007, 07:57 PM

Quote:

Originally Posted by Norrrrrrrrrrrrm

I have heard from from many people tell me many different things when it comes to charging a rechargeable battery. Some say drain till it's ka-put, other say when you first sense power loss revive the little bugger. My question is, who here knows what the real deal is and why?

This may answer your question.

Mike Finley · 10-31-2007, 08:07 PM

There is one sure way to find out.

Google + Manufactuter of your batter (Dewalt, Milwaukee... ect..)

Go to manufacturer's website, search around for battery info on it.

Read manufacturers recomendations.

What da ya think the manufactuer is lying to everybody about how to get the most out of their batteries?

mdshunk · 10-31-2007, 08:15 PM

I have my chargers hooked up in the truck, and just throw the batteries back on the charger when I'm done at each call. If it shortens their life, I really can't tell. I need to have good charged batteries in much the same way I need other depeleteable materials, so I really don't have a choice. I never know what the next service call holds, so I need them all filled up.

Tom R · 10-31-2007, 08:59 PM

Quote:

Originally Posted by Norrrrrrrrrrrrm

I have heard from from many people tell me many different things when it comes to charging a rechargeable battery. Some say drain till it's ka-put, other say when you first sense power loss revive the little bugger. My question is, who here knows what the real deal is and why?

It varies, - - you have to treat each kind according to what the manufacturer says.

For instance, my Porter Cable drill batteries want to be charged when the even 'start' to lose power, - - but you also need to let them cool down to room temperature first, - - and the charging operation should be kept as near as possible to room temperature also.

Chris Johnson · 10-31-2007, 09:38 PM

I use Milwaukee and they say to drain them as much as possible, well it's kind of hard to completely drain them when your in the field. I bought one of their 3 bay chargers which is 'suppose' to drain them completely then recharge. I still only get 8-10 months out of an average battery

Catoctin Timber · 11-01-2007, 10:08 AM

I hear a lot of people complaining about batteries not lasting. I have never had to replace batteries on my cordless stuff. READ the instruction manual that comes with the tools. DONT charge off of extension cords or generators unless ABSOLUTLEY necessary. Dont charge in extreme hot/cold. Seems to work great.

aWorkaHolic · 11-01-2007, 10:34 AM

I use Dewalts XRP 18v. I found that it's a hit and miss with them. Some Batteries will last months and some just seem to die after warranty. All in all I still get good usage out of my tools.

A W Smith · 11-01-2007, 01:07 PM

Friend of mine uses the new Makita 18 volt. Took them to Makita USA in Dayton and they put them in some sort of device which told them how many times they were charged and thus weather they were still within the warranty.

mickeyco · 11-01-2007, 01:52 PM

Depends on what type of batteries they are and if they have a "memory". On the old Ni-Cads I rubberband the switch on till they are low, let them cool and then charge. I still have an old Makita 7.2 volt drill and battery from 1984 or 85 that still works.

daArch · 11-01-2007, 04:58 PM

You are probably getting different answers because there are many different types of rechargables.

The three major types we see for tools, phones, cameras, etc are Ni-Cad, Ni-MH, and Li-ion.

Ni-Cads are the ones most associated with "memory" - although this is a misnomer. If a ni-cad pack is partially discahrged and then "topped-off" it will develop what is called "memory". Ni-cads "should" be discharged to 1.1 v per cell each time to counteract this "memory" phenomenon. However if they do seem to loose capacity, they can be "cycled". Meaning, discharging the pack at about 1C until each cell is 1.1 volt and then slow charging (C/10 for about 18 hours). Ni-cads CAN take abuse and survive. They can be discharged well below 1.1 v per cell and survive. They can also withstand the heat of being overcharged, although battery life will be diminished somewhat

Ni-MH can more sensitive and will not take complete discharge or the heat of over charging. They, however, are "not known" to develop "memory". They can be repeatedly "topped-off" after partial discaharge. I still like cycling my Ni-MH once in awhile.

Li-Ion are the MOST sensitive. I fried a $50 camera battery by leaving the camera on (no auto shut off) just ONCE. After being conditioned, li-ion's are the least susceptable to "memory". They can be "topped-off" at will. Conditioning a li-ion means discharging til the "recharge" notice shows and then sticking it in the charger until charged - do this three times in succession. I do not mess with li-ions. I use ONLY the charger that came with them. (I have a real nice smart charger for my ni-cad's and ni-mh's)

And now my RC buddies tell me about Li-Po (lithium Polymer) that I know NOTHING about, except that they can be molded to fit any shape - great for hi-tech devices and Electric RC planes.

There is a lot of GOOD info on the net for each battery type. The RC Industry has been using light weight, high capacity, high reliability batteries for decades. If you stumble on a site that seems to be geared for the RC hobby, you will know why.

Unless you know a lot about batteries and have very smart charging systems, PLEASE use only the charger that came with the battery pack and follow the directions.

Hope that helps

kingsmurf · 05-01-2008, 02:05 AM

my advice from my own experiences are that I always hook new batteries up to an purly resistant load and drain'em a couple of times minimum...draining them slowly until dead works great

A MUST FOR THOSE PESKY CORDLESS PHONE BATTS . .I just use 'gator clips and some simple bulbs to kill'em a few times

I have a set of marine batts I power all of my power tools with on construction sites . . .I do the same with them

I have used extension cords for decades to power my chargers
BUT NEVER NEVER hook them to box wave or mod sine wave TYPE CONVERTER . . . . . . .BOTTOM LINE there is that the chargers
require nothing more than the Correct VOLTAGE AND THE correct WAVE

BUT BATTS DO DIFFER IN TYPES..always good to run'em down and re-charge if they have been sitting a good while

XanadooLTD · 05-01-2008, 08:34 AM

Hilti has the reset button on its chargers that is supposed to reset the battery so that you never have this problem. I have a 12 volt little drill that has never once killed the two original batteries. When i think they are going to die or are dead i hit the reset let it sit for 24 hours, then charge it up. Hasn't failed yet. 18 and 36V hiltis aren't old enough to have tested this.

Greg Di · 05-01-2008, 10:35 AM

We had older milwaukee chargers on our FD's rescue truck. When the truck is in the bay, it's plugged into AC power so the batteries would always be charged. Allegedly.

What we found out is that every time the truck rolled out and came back in, the batteries were going into drain mode and the on/off charger cycle smoked all the batteries in about a month. Go figure.