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Lithium Ion Batteries
A search of the web
2021-12 ref. Lithium Ion Batteries, especially for recovery of
over discharged batteries, & what risks in recharging,
& what charge current for 18650 cells.
External Links
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General, Not Specific To Deep Discharge Recovery
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Battery Manufacturer Product Specific
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Non Battery Manufacturer - Users &
Researchers
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Deep discharge recovery
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Forum
- "Mechanism of the entire overdischarge process and
overdischarge-induced internal short circuit in
lithium-ion batteries"
www
. nature . com / articles / srep30248
- Overdischarge and Aging Analytics of Li-Ion Cells -
Journal of The Electrochemical Society - PDF
iopscience . iop . org / article / 10.1149 / 1945-7111 /
aba00a
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www . einhell . de / en - de / blog / workshop / battery
- guide . html
"Our Power X-Change chargers are equipped with a
refresh mode. If a battery is plugged into the charger
whose deep discharge is not yet too far advanced, the
battery can still be "saved" in many cases. The charger
charges the battery very carefully until the minimum
charge level is reached again. It can then be charged
again as normal."
- Deep Discharge research PDF on request
www . researchgate . net / publication / 311499287_Li -
Ion_Battery_Deep_Discharge_Degradation
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maker . pro / custom / tutorial / what - is - deep -
discharge - build - a - simple - circuit - to - protect -
batteries
"when the battery undergoes over-discharging, it is
very difficult to recharge it because the internal
resistance of the cell has increased ... example of a
widely used 4.2V Li-Po battery when the voltage reached
below 3.7V there is damage in the internal resistance of
the battery. The damage becomes significant below 3.0V.
Charging these batteries take tons of time. For charging,
a smart charger is a mandatory requirement. Initially,
for 0-3V of the battery, charge at 1/20 C charge rate. Do
not leave the battery unattended and also touch it
frequently and check if it's not getting hot. If so,
lower the charge rate. When the battery is charged at
3.0V, increase the charge rate to 1/10 C rate and after
3.7V, you can charge it at higher 1/2C rate until
4.2V"
- How to Revive Lithium Ion Batteries
sciencing . com / revive - lithium - ion - batteries -
5982537.html
you shouldn't attempt it with batteries that have
been below 1.5 V for over a week ... Return the battery
into the lithium-ion charger and give it a full charge,
which should take around 3 hours depending on what type
of Li-ion battery you are reconditioning. Some chargers
automatically progress from recovery mode to charging, so
on these devices you can just leave the battery in place
throughout. Next, discharge the Li-ion battery again in a
device that is going to put a heavy load on the battery,
like an LED flashlight. Seal the Li-ion battery in an
airtight bag and put it in the freezer for about 24
hours, ensuring there is no moisture in the bag that
could get the battery wet. When you take it out of the
freezer, let it thaw for up to eight hours to restore it
to room temperature. Place the Li-ion battery in the
charger and charge it fully. Hopefully, its performance
will improve, it will take a charge again and last longer
between charge cycles.
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www . dell . com / community / Laptops - General - Read -
Only / Best - way - to - charge - discharge - the -
battery / td - p / 3275322
"The battery can become un-useable if discharged too
deeply. It is not necessarily shot, but the circuity
disables the charging function, as recharging a deeply
discharged Lithium battery can be dangerous."
Editor's own batteries:
- Sony Energytec US18650 S STG
(Blue colour)
10 in a pack saved from a dead Compaq laptop. pairs of 2 in
parallel, stored for years, @2021-11 4.08 V on each pair,
except 1 pair (end of serial stack with red wire) at 2.95
V
- Panasonic Lithium Ion
CGR18650 Matsushita Electric (Pink)
15 in a pack from Black laptop.
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Dell From a Dell Latitude E6530 laptop gj@ later gave jhs@ 2021-11, battery labeled: 11.1V
60Wh.
Laptop battery light gave some unusual flickering, BIOS
showed zero charge even after plugged in hours.
Drilled out the plastic rivets, squeezed the case with
movable axle pliers, to stress the glue join along the
case, finger nail at corner, 2 screwdrivers alternately
working along to crck the case shell apart.
6 orange colour cells, Cells in pairs of 2 parallel wired,
3 pairs in series.
Cells labeled LG ABC21865 L332K276A2,
2 thin wires: 1 green (@ 4V), 1 yellow (@ 8V), 1 red thick
wire (@ 12V) going back from each pair of cells voltage
stage to PCB controller of battery pack. + 2 thin black
wires adjacent, probably a temp detector. Battery PCB
marked Dell MaCallan
Cell voltages (- end) 0.922 V , 1.035 V , 0.906 V (+
end)
Recharging: I used 50 mA into all 3 in series, within
minutes they each went to 2.4 Volts
Elapsed
Hours:Mins |
Cell
Voltage |
Internal
Resistance |
0:00 |
2.40 V |
|
1:30 |
3.08 V |
|
2:00 |
3.13 V |
|
2:30 |
3.25 V |
|
4:00 |
3.46 V |
1.8
ohms |
4:45 |
3.57 V |
|
5:15 |
3.57 V |
|
5:30 |
3.57 V |
|
6:15 |
3.62 V |
|
7:00 |
3.64 V |
2.27
ohms |
8:00 |
3.58 V |
0.56
ohms |
8:02 |
3.57 V |
0.33
ohms |
9:00 |
3.58 V |
0.33
ohms |
10:30 |
3.61 V |
0.33
ohms |
11:00 |
3.62 V |
0.39
ohms |
13:00 |
3.67 V |
0.33
ohms |
HH:MM |
v.vv V |
_.__
ohms |
Internal Resistance = V-on-charge = V-open-circuit / 50mA
charge current / 3 (cells in series)
Later when higher voltage, I will return it to standard
charging on laptop, then as it may have lost capacity, I
may do a discharge test, & or swap the cells for Sony cells
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