The plastic casing for the pack was solidly welded together and had to be cut open with a dremel tool and an abrasive blade. Care taken not to cut too deeply and cut into the cells themselves. Once open I found nine 18650 cells. Pink LG LGABD11865 cells in a 3x3 arrangement. They measure 4.13 volts!! Quite usable and apparently almost fully charged. I wonder why this was discarded.
These are 3000 maH cells made by LG. They are dubbed the LG "D1" cell (there is also an HG2 that can supply up to 20 amps). These can supply up to 5.8 amps, not that ever intent to use them that way. They are 4.35 volt cells (so I can use the 3.8 volt setting on my XTAR VP2 charger). They work just fine charged to 4.2 volts (but you sacrifice about 300 maH).
Actually I am having some issues with these. They seem to loose charge fairly quickly and one got quite hot while charging.
This was easy to disassemble and was made from 6 flat "soft pack" cells. It was manufactured in 2009. The cells are in a 2x3 arrangement and the center pair were bulging badly!! When disassembled the bulging center cells measured 0.45 volts and were of course discarded. The other four cells though measure 3.57 volts. So they are fully discharged, but safe to recharge!
These are in two pairs, each is glued together and wired in parallel, so I will keep them as "matched pairs" and continue to charge and use them together. I am actually quite surprised that it looks like I will get two useful batteries out of this old pack.
This pack was easy to disassemble by twisting it and prying with a screwdriver. Inside are 8 18650 cells with green skins, labeled "+FP 18650 1800mAh 140112-". An earmark of this being a low quality pack is no thermistor inside. The cells are in a 2x4 configuration. One parallel pair measures 0.65 volts and I discard these. The other 6 cells measure 3.6 volts! This looks like this pack will provide 6 entirely useful cells, although low capacity no-name generics.
This pack was a bit more trouble to disassemble, but after making a couple of cuts with an abrasive disk, a screwdriver popped it open. It has two thermistors inside! Inside are six 18650 cells with red skins and almost invisible markings: "Sanyo L UR18650A R2112 P20B" The cells are in a 2x3 configuration. The pairs measure 3.09 volts, 1.71 volts, and 2.50 volts.
These are 2150 mAh cells, 4.2 volt charge, 3.6 volt nominal. They are rated to deliver 2.15 amps.
The usual rule of thumb is to discard cells measuring below 2.5 volts, so I should discard the center pair. But I decide instead to mark them with two black dots and charge them up.
Later, I put one of the 1.71 volt cells in test mode on the Vtar Dragon. It began to get quite hot, so I removed and discarded it. I located its brother after this and also discarded it without any testing.
I mark the 2.5 volt pair with single dots. I charge the 2.5 volt pair with care and attention. The 2.5 volt pair is up to 3.12 volts after 5 minutes on the VTAR charger, up to 3.26 after 10 minutes -- and staying cool. 3.5 volts after 20 minutes. 3.54 volts after 45 minutes. Later though when charging this further, they got quite hot and were discarded. I have enough cells that act nicely that I don't need to take any chances with these.
This looks exactly like the other two ASUS packs, but it has a higher mAh rating, which is because it has better cells inside. The cells (six of them) have grey-silver skins marked "LGABB41865 K197G166A1". This looks like an older but higher quality pack than the two above, not just because of the cells, but the build is more solid. They measure 2.5, 3.46, and 2.8 volts, so all the cells are potentially usable.
These are 2600 mAh cells made by LG in Korea. They are nominal 4.2 volt cells.
The cells with dots got very hot when recharging (one reached 150F) and were discarded. In fact all 6 of these cells got hot enough to worry me and have been discarded.
Also easy to open, identical to the above, but the cells are different. These cells have blue skins and are marked "EPT 18650 2000 mAh 3.7 volts 2014". They measure 2.7, 2.0, and 2.7 volts. It looks like these are made by Shenzhen EPT Battery Co. Ltd in China. I toss the cells that measure 2.0 volts.
Inside are 9 cells with red skins in a 3x3 arrangement. No Thermistor. Cells labeled "NAQM4C9". They measure 3.6, 1.2, 3.17 They have nearly invisible markings UR18650FM N11A Sanyo. Looks like I get 6 cells that are potentially usable. The three cells that measure 1.2 volts get tossed.
Inside are 12 Sony (imagine that) US18650GR cells.
All measure about 3.66 volts -- so why was this thrown away?
These are green 2200 maH cells that will charge to 4.2 volts.
I have marked these 2017-11-A
Tom's electronics pages / tom@mmto.org