Rebuilding a 600 battery

[wkw]

So a while ago I tore apart three 600x batteries, they didn't work. I threw out the cells. I have noticed that, because one was broken horribly, and the other I stripped out to just have hollow on my 600x, I only have one with functional circuitry

http://i237.photobucket.com/albums/ff44 ... 4260a9.jpg

I'm wondering, if I get regular rechargeable batteries and put them in, would it function and charge properly? What kind of batteries would I need?
Thanks

[rkawakami]

I would expect that the charging circuity has been designed around the typical 18650 lithium-ion battery packs. If you attempt to put in "regular" rechargeable batteries (I'm guessing you mean the off-the-shelf nickel-metal hydride type), your safety, or that of the laptop it goes in, is at risk from leakage or explosion.

Even if you use the same type of cells, I would not recommend a re-cell operation unless you are very familiar with the handling of lithium-ion batteries; namely, a possibility of them exploding if excessive heat is applied. In other words, DO NOT try soldering wires directly onto the ends of the batteries. In the past I have sent some dead 600X packs to http://www.batteryrefill.com/ and had them re-celled. What comes back is not very pretty but they were functional. Over the years they have had a hit-and-miss satisfaction rate among the members here. Use the following Google search:

600 batteryrefill.com site:forum.thinkpads.com

[wkw]

Well I've been buying the rechargeable lithium ion energizers in the past, and wasn't sure if the 600x needed li-ion or the nickle metal hydride ones. But I was not intending to solder them, at least initially. At most I would use some really good tape to hold them in.
http://i.tfcdn.com/img2/NjMHVk4ABcHRCcA ... */fyVMtP8A
Do you think those would work?

[rkawakami]

In a word, "no". The original Li-ion cells output about 3.7V apiece. Those AA batteries are around 1.4V each. While they say "lithium", it's not the same chemical technology as lithium-ion. You need to replace the original cells (type 18650) with the same kind. They can be higher in current capacity (mAH) but they should be physically the same size and use the same battery chemistry as the originals.

[wkw]

Alright, I see. Not going to buy some to try this, then.

But in theory, any lithium ion battery that is 3.7v would work, correct?

[rkawakami]

In "theory", yes. But you have the physical limitation of the insides of the battery pack. Using smaller Li-ion batteries generally means less current capacity and therefore, shorter running times. I don't know enough about the charging circuit to say how much deviation from the original specifications is allowed. Here's an old site about the 600-series battery that I've referenced before:

http://www.milnoc.com/TP600Battery/index.html

[Radioguy]

Hmm, am I to assume the 600x compatible battery doesn't have a charging circuit that goes dead once the chain of cells are broken?

[rkawakami]

I believe that's the case, but then again, I have not tried to re-cell a pack myself. And along those lines, I'm not sure if there's anything special that needs to be done to the charging circuit / monitor that tells it fresh cells have been installed.

[Radioguy]

I wish that were still the case with more recent model ThinkPad batteries.

[Majestic]

Alright, I see. Not going to buy some to try this, then.
But in theory, any lithium ion battery that is 3.7v would work, correct?

I never repacked a laptop battery, but I do use 3.7v lith-ion batteries in other projects. I get them through an on-line retailer in China. Prices are good, shipping cheap and delivery is generally 10 to 14 days to my home in the midwest (try to avoid ordering during their holidays).

http://dx.com/c/electrical-tools-499/batteries-400

If your are interested, what I would suggest is to measure the length and width of the batteries in your battery pack. A caliper works best for an accurate measurement. Then review the product listings for the various batteries offered and find one of similar size. The product's review will also offer some insight into folks that may have used that battery for repack purposes. They offer both protected and unprotected batteries for sale and I would recommend the "protected" version if available in your needed size since the protection prevents over and under charging of the battery. They also offer batteries with a solder tab already attached to the battery so that you do not have to solder directly onto the battery when repacking.

[Radioguy]

Given the topic, brand names like "TrustFire" and "UltraFire" don't inspire confidence.

Frankly, batteries and flash media are items I avoid like the plague at DX.

[wkw]

Hm.. Looking at the prices of the cells, it would be far more economical to buy a refurbished battery then to buy the individual cells.

[loyukfai]

Depending on the cells used... Japanese 18650 cells aren't cheap... BTW, I've heard that one has to keep the cells connected during re-build, or the controller chip in the battery will self-kill.

Cheers.

[wkw]

You mean to the TP battery?
That would be a problem, because the battery shell has had the cells out for a good six months now!


You're saying that if the battery pack doesn't have cells in it, then the charging circuit shuts down making the battery pack unusable, even if the cells are replaced?
Daww :\