Is it possible to switch macbook charging at 220v input?

Question

Do it yourself

Hello. The battery on the MacBook Pro 2015 is swollen, I’ll change it, to prevent it I want to keep the charge level at 80%.
You can’t do this with software, so I’m going to turn off the charge when it reaches 80%, turn it on when it drops to 78%. Do you think this is a normal range?
I will switch from a bash script, reading the current charge level and sending a command to turn on / off the Sonoff socket into which the MacBook charger is plugged.
Another option is to cut the wire at the charging output and switch there, either through the sonoff relay, or I myself throw in a similar device.
There are two questions to which there is no unequivocal answer
1. delta 2% - is it normal for a battery?
2. switching at the input (or output) of charging - is it normal?

Update.
In the process of research, I found a way - charge to the desired level (60%), turn off magsafe2, close the middle pin with tape, connect magsafe2. As a result, the laptop is powered by the adapter, the battery is not charging, when you click on the battery, Battery is not charging

Answer 1

Can be adjusted by software
https://github.com/davidwernhart/AlDente

Answer 2

Do you think this is a normal range?

No, this is nonsense. The battery controller will decide what and when to charge, engineers are not fools.
The rest of the plan is just bullshit. Don't suffer bullshit.

Answer 3

the battery swelled up on the 6th year of use, right?
just replace and move on
there is no need to invent anything for
sure, apple engineers are not fools and have made reasonable battery charging schemes taking into account many conditions that you may not be aware of.

Answer 4

Good afternoon! Once it was necessary to install a double socket near the bed. A friend advised me to contact this online store at https://tdm-elektro.ru/ . I ordered a double socket 2P + Z 16A 250V from Lama for 159 rubles. The quality of the outlet is good, easy to install, connection is convenient. Installation and connection only took 20 minutes.

Answer 5

2. switching at the input (or output) of charging - is it normal?

In my opinion, both from the side of the battery and from the side of the charger, it all makes absolutely no difference.

1. delta 2% - is it normal for a battery?

And here there is a nuance, and it is connected with how to calculate the battery life. As you know, the main criterion for a resource is the number of cycles that a battery can endure during its lifetime. This figure may turn out to be fixed, and not only by the chemical wear of the battery cells, but also directly, by a special counter in its controller. Of course, at a 2% delta, the cycles will be very short, and therefore a fixed amount of cycles will be depleted very quickly. Personally, for these reasons, I try to discharge the battery at least up to 50% before putting it on charge, i.e. stretch the duration of each cycle, but this is not always possible.
Common sense suggests that the above considerations may turn out to be nonsense. What if it's not nonsense? We do not have exact information on this.