Sony Konions from Makita Packs as Laptop Batteries?

[fitek]

I have 2 Makita packs that wont charge anymore. I have a Thinkpad which runs for 30 minutes on its battery. This is the third battery. The replacements all use crappy cells. Pack voltage is 14.8v-- I assume 4s2p. Any issue with using cells from the Makitas?

 

[amberwolf]

Probably not, if they'll fit. I don't recall what the Konion charge voltage is, though, vs that of the typical LiCo that's in the laptop cells.

 

[kfong]

I just repaired my nieces laptop with them. So far so good. Will know in a couple of weeks on how well it holds up.

 

[liveforphysics]

While they will work fine, cells with double the energy density are available in the 18650 package. This literally translates to 2x runtime.

NCR18650 in 2.9Ah format is a nice lappy cell.

 

[SamTexas]

I have 2 Makita packs that wont charge anymore. I have a Thinkpad which runs for 30 minutes on its battery. This is the third battery. The replacements all use crappy cells. Pack voltage is 14.8v-- I assume 4s2p. Any issue with using cells from the Makitas?

I wouldn't do that. The Konions have higher discharge rate (which is not required in laptop use) but lower energy density. Best bet would be to look for a "bad" laptop battery pack and retrieve the good cells. Laptop cells are Lithium Cobalt and have a 2.5Ah rating or higher.

 

[kfong]

I should of mentioned in her case, there were only 4 cells with 4 blanks. Since I had spares and didn't wan't to spend any money on it. I just opted to go that route and fill it with 8, so it should be close to what she had. I'm hoping these will last longer in useful life since the originals seemed to have crapped out in 2 years.

 

[fitek]

Good point on the energy density. I would rather keep the Makitas for EV use. They are out of warranty now, though they stopped charging while in warranty (wedding got in the way...). There is a Makita service center across the bridge from me, I wonder what the likelihood of getting the packs repaired or getting the service center to give me some packs to cannibalize is...

I'm willing to buy other cells, the Panasonics seem a bit pricey? I could go for lower capacity.

My original Thinkpad pack was 4.2ah or something like that, and I got almost 6 hours of battery life when new. That means each cell was 2100mAh. With 2900mAh... hmm, that'd be nice to get over 8 hours of battery life Especially compared to 30 minutes...

BTW, the original pack "died" due to BMS failure. I called Lenovo since I shelled out for the super duper warranty but the battery was 13 months old and they warranty batteries only for one year. They said it died because I abused it, running it down too low-- I called BS, since it suddenly cut out and stopped working, but they didn't care. Awfully nice of them...

 

[amberwolf]

If they have a BMS that is designed right, it's not POSSIBLE to run it down too low because the BMS ought to prevent that. So abusing it means that they didn't build it right in the first place, and that, to me, puts the problem back in their lap.

Otherwise, how in the world would any customer know what "too low" is? Does the warranty and user guide for the laptop give a specific level (displayed on the laptop screen clearly at all times) at which one must not go past? If not, there is no way for a customer to know when to stop until the laptop shuts down for low power levels, as pretty much all of them are designed to do.

 

[fitek]

Heh, it went like this: The CSR asked me if I'd ever let the laptop run down to 0%. I said yes, it had happened once, just recently before the battery stopped working. He said, "Oh, you damaged it then." I told him batteries don't die suddenly; electronics do, and the electronics in battery probably died. Regardless, it was out of warranty anyway. But anyway, this is out of scope for an EV battery forum

 

[grindz145]

Unless your some kind of extreme laptop overclocker.... 8)