Hello All; got my cf28 from fleabay...

Greetings to all...

I got my cf28 from fleabay this week. Was advertised with cd, wireless, GPS, floppy drive, WinXP, and touchscreen. Well, it came with an external USB CD (No native drive or caddy), no wireless, no floppy drive unless it's hidden in a place I have yet to find, and a Chinese made USB module. The computer case is beat up pretty good and a dremel tool was used generously to remove some kind of company markings. But... the touchscreen works perfectly, the LCD has no scratches, and the keyboard is clean. The battery was advertised as not holding a charge and indeed, all the bat symbol would do was flash red as soon as I plugged in the power supply. I disassembled the battery case and hooked up 16 VDC to the + and - leads after desoldering from the control board. Let it cook for 4 hours, put it all back together, and let the computer charge it for the rest of the night. Now it has 4 hours + capacity. So I did get that bonus . I'll be spending some time here reading and learning more about my new toy which, by the way, is destined to be the heart of my nav system on my boat... Hope to meet more of you folks here and look forward to learning lots from y'all....

regards,

N_R

 

Glad to add another to the Toughbook crowd. Welcome to the forum!

 

I'm interested in your battery hack. It sounds very good!

 

i've got a couple to experiment with as well!

 

Welcome. I'd like to hear more about your battery hack as well.

 

battery! battery! battery!

 

Hey! You stole my thread title!

I'm new here too, welcome!

 

I've heard about doing something similar to this but with the battery still put together. Basically doing the same thing but without unsoldering the battery control board. It didn't work... Now I know why. I have about 15-20 dead batteries or ones that only hold 10-15 minutes worth of charge. I bought a bunch of Li-Ion batteries to rebuild them but I think I'll try this method first. I'm sure this hack won't work on all batteries but if it works on half of them I still save $45 per battery. (Cost of replacement cells)

Excellent tip though... Good Rep to you!

 

Hello, all!

I will go over exactly what I did together with observations.

The battery came with the computer DOA. I do not know if the battery was simply left in storage too long or anything else. Plugging in the powersupply made the orange 'charging' LED light up. After about ten seconds, it would revert to blinking red. I did NOT know about the BIOS battery refresh utility at the time and therefore do not know if that would have 'fixed' anything. (Thanks to several of you, I am now aware of that utility!) I dis/reconnected the power cord several times over a period of some hours to try to get something other than a blinking red LED, but never got any other result.

I have several loose Panasonic lith/ion batteries and resolved to take the battery pack apart, find and replace any weak cells, and try again to have the computer take care of charging it up.

I removed the pack and carefully split the casing along the seam with a carpet knife. Inside the pack were nine cells laid out in three groups and a small circuit board. Each group consists of three cells connected in parrallel, and the three groups are connected in series. I desoldered all the wires leading from the circuit board to the cells (One each of white, green, red, and black wires.) I then measured the voltage of each triplet group and got 2.1, 1.9, and 2.3 volts. Very low indeed. No signs of any overheating or leakage.

I then decided to 'play' a little and went to my junk box to find a resistor. I picked out a 20 Ohm, 9 watt wirewound ballast type resistor. I then used one of my 16 volt IBM laptop power adapters and hooked it up to the battery end terminals with that wirewound resistor in the circuit to limit draw. It got uncomfortably warm, but not to the point where I was worried about it. I left that setup to charge for about 4 hours. When I came back, the battery pack was now reading a total of 11.3 volts. It was not warm from the charging although the resistor was still running hot. I decided that maybe I would just put it back together again without any further ado and try it in the computer again. I did so and this time when I plugged in the toughbook power supply, the battery light remained in the orange 'charging' mode. I left it overnight and in the morning, the battery LED was green.

A quick check showed that the battery now had 4 hours and some minutes capacity. Several running tests over the past couple of days confirm that capacity and the battery doesn't seem to be self discharging any. As I said, I do not know anything about the age or history of that battery, but I suspect it might be a NOS (New Old Stock) battery that sat around for way too long without being charged. I rather think that if it were that easy to revive an OLD USED battery, we'd probably already know about it... I kinda think I maybe got lucky with a NOS battery... I hope this answers your questions...

Regards,

N_R

 

I removed the control circuit from the batteries to prevent the possibility of damaging it with my experimenting. I suspect that the batteries which hold only fifteen minutes of charge are prolly gonna need some cells replaced, but...... You might try cycling them several times manually using something like a small 12 volt panel bulb to completely run them down and then recharge them like I did. I plan on trying this with one of my IBM batteries which holds only about 20 - 30 minutes. I don't have any replacement cells for it:-( Where can you get brand new cells?

N_R