How does a battery wear out?

Question

Batteries

There are several banal questions about batteries for different devices.

• Up to what place is the battery considered suitable in terms of the number of charging cycles declared by the manufacturer - after all, it can significantly lose capacity, but will continue to work? What does this indicator consist of for a laptop battery, the manufacturer of which promises 150 cycles? Does the number of charge cycles correspond to a full discharge / charge or the number of connections or something else?
• Do I understand correctly that he will still die in a couple of years, regardless of the number of charge cycles?
• Which is better: to charge the phone, for example, all the time, to charge as it reaches 70-80% discharge or when it is completely discharged?
• Why is it recommended to discharge incompletely charged batteries for several days?
• Which batteries are sensitive to deep discharge? How and which behave in the cold? Heat?

Answer 1

It is not recommended to wait for a complete discharge, 70-80% of the discharge is the most. Unless of course we are talking about Li-ion.

Answer 2

For example, I adhere to a very naive analogy with a person: not to discharge much (who likes to exhaust himself to zero every day until the splitting of ADP), to give food to the full (if he is starving, then over time he will not be able to eat as much as he could before and will have to “train”), do not overheat, do not overcool.
So far, my batteries last much longer than those of my friends.
In general, it would be interesting to deal with this matter in depth (at the physical and chemical level).

Answer 3

I'll put in my 5 cents:
1. Most modern laptop batteries use Li-ion batteries. The number of charge / discharge cycles, up to a loss of 20% of capacity, is 350-650 cycles.
Unfortunately, I can’t give a definition of cycles, but basically this is true for a full discharge charge cycle.
2. It will die, but it will take several years, provided that you discharge and charge the battery again every 4-6 months. Why? - because batteries of this type self-discharge at room temperature by 5-10% per month. The optimal charge for storage is 40%.
3. I can’t provide reliable data, but I think that it’s better to completely discharge and then charge (After all, xs, what is this charge / discharge cycle). This throwback in my brain was left over from Nickel Metal Hydride (Ni-MH) batteries, which had a memory effect. Li-ion, however, does not have it.
4. I did not understand the question.
5. Deep discharge completely destroys the lithium-ion battery (like most batteries except Ni-Cd). Well, the temperature regime varies from -15 to +60. In severe frost, they practically stop working.

Answer 4

Can you be a little more specific about why?

Answer 5

Up to what place is the battery considered suitable in terms of the number of charging cycles declared by the manufacturer - after all, it can significantly lose capacity, but will continue to work? What does this indicator consist of for a laptop battery, the manufacturer of which promises 150 cycles? Does the number of charge cycles correspond to a full discharge / charge or the number of connections or something else?
As I understand it, this is charging-discharging. But 150 is not enough, somehow strange. It will be interesting to read the answer to this question in more detail)
2. Do I understand correctly that he will still die in a couple of years, regardless of the number of charge cycles?
Yes, if the battery is not used, it still wears out.
3. Which is better: to charge the phone, for example, all the time, to charge as it reaches 70-80% discharge or when it is completely discharged?
When fully discharged, this is how the battery "trains", if I'm not mistaken, and there is less wear.
It is interesting to hear the answers to the remaining 2 questions, somehow I didn’t think about it before :)