Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [lithium-ion]

Questions regarding Li-ion (lithium-ion) cells and batteries, including proper charging, protection, and usage.

Questions regarding Li-ion (lithium-ion) cells and batteries of all formats (pouch ("LiPo"), 18650, and other small cylindrical, small, and large prismatic) and chemistries (LCO/cobalt, LFP/LiFePO4, NMC, LTO/titanate), including proper charging, protection, and usage.

1495 questions
12
votes
2 answers

Charging and Using a Li-ion battery simultaneously

My system requires a power which is supplied by a Li-ion battery. However, I need to keep this battery charging at all time so it won't die. Is it possible to connect the battery to my system and also have it connected to the MAX1555 which is…
Caspian
  • 305
  • 1
  • 2
  • 10
10
votes
2 answers

Maximum *charging* voltage for Li-Ion battery

I'm implementing a CC-CV algorithm for charging a li-ion battery. I'm confused what is the maximum allowed charging voltage during CC (constant current) phase. All application notes and datasheets, I've found state that charging in the CC mode…
bvr
  • 125
  • 1
  • 1
  • 6
9
votes
3 answers

Li Ion battery reconditioning?

My company have thousands of new Li Ion battery that is stored in ambient temperature for 3 years. Middle management then decided to manufacture products with these batteries. I had already tested them, their current capacity drop to 85% rated. Then…
Jason Han
  • 1,750
  • 9
  • 22
7
votes
2 answers

How plausible is the claim about a 200 kW battery solution?

Following this question posted on Aviation:SE: Does the ARCA hoverboard violate known limits on small-diameter electric fans? which is related to a hovering board described on the vendor site: (source) I would like to assess the claim this device…
mins
  • 376
  • 1
  • 9
5
votes
5 answers

Managing high power battery pack voltages

I have a few upcoming projects that will require some higher power battery applications where voltage swing needs to be limited. Both will be powering electric motors. The first on will be ~1.3-1.5 kW, 24 V motor (7s21700 battery). The second will…
Archer Thompson
  • 73
  • 4
5
votes
2 answers

Standby power using a lithium cell

I have an application for a backup power supply, which requires guaranteed energy available, but very infrequently, think burglar alarm. I would naturally gravitate towards lead acid as it has a well defined float charge protocol. However my client…
Neil_UK
  • 166,079
  • 3
  • 185
  • 408
4
votes
2 answers

Connecting four 18650 batteries in series without BMS

I have four batteries (18650) 3.7 V each, and I want to connect them in series to get around 15 V. Can I do that without having a BMS? Just directly connecting them together? Note: I do have a charger specifically to charge this type of batteries,…
alaa alnajjar
  • 41
  • 1
4
votes
4 answers

Lithium battery charging-undervoltage

I know that the maximum charging voltage for lithium ion batteries is 4.2v. I also know that charging a lithium ion battery involves a constant current and constant voltage phase. But what will happen if I continuously charge a lithium ion battery…
jasper samson
  • 41
  • 1
  • 2
3
votes
2 answers

Lithium Ion Battery Pack - Looking to calculate watt-hours from V1 to V2

I've got a 2S4P Lithium Ion 18650 pack (that's 2 sets of 4 cells in parallel where each set is in series). These batteries can be changed to typically around 4.1 or 4.2v and can technically be discharged low (2.5v), however the wider this range,…
Cody Smith
  • 33
  • 3
3
votes
2 answers

Simplest possible circuit for charging a li-ion cell

I want to create an ad-hoc single cell li-ion charger. I have a buck step-down that can supply 4.2 volts. If I connect a 1 ohm resistor in series with the lithium cell, the current should go down to 0 when the battery is also at 4.2 volts. A 1 ohm…
frodeborli
  • 251
  • 1
  • 5
  • 10
2
votes
2 answers

Can I mix new and old lithium-ion cells

I wish to start a lithium-ion battery bank but want to add additional Li-ion cells once I establish my power needs. So can I add additional Li-ion cells after say six month to a year?
john Done
  • 21
  • 1
  • 2
2
votes
2 answers

Clear cut thing to do when 18650 Li Ion Cell Has Been Overdischarged

I think close to everyone knows over-discharge of Lithium ion cells is bad news, creating fire and chemical burn hazards. These are my cells I accidentally over-discharged two Lithium Ion cells. What I would like to know is whether that should be…
ScottyJ
  • 31
  • 3
2
votes
3 answers

Replacing li-ion cells in handheld drill battery

I am considering to replace the 18650 battery cells in a 3S1P 11.1V cordless drill battery pack rated at 1300mAh, with three 2200mAh cells from a salvaged laptop battery pack. One of the four cells in the laptop battery pack was bad (0V), but each…
frodeborli
  • 251
  • 1
  • 5
  • 10
1
vote
1 answer

How to prolong a lithium battery life mathematically?

How to use a lithium battery so that it gives as much energy as possible in total during all battery discharge events from the moment of purchase until the moment when its performance drops to some unacceptable level? What percentage of discharge is…
Eimrine
  • 21
  • 1
1
vote
2 answers

On/Off switch for Li-ion battery pack

Is it ok to tie the battery pack (in my case 3s1p) to a SPST switch to turn it on/off or I should need a series resistor after the switch to limit current and a big fat cap to smooth the on/off transition? Something like this: simulate this circuit…
Status Re
  • 223
  • 1
  • 7
1
2 3 4