As electrical engineer working with batteries I can say a few things:
1) Discharging to 0% and charging to 100% as a "calibration" is pure bullshit. Does nothing good for your battery and only harms it because li-ion batteries doesn't "like" to be discharged to low capacity. I wouldn't say 0% capacity because battery management system probably turns of the phone before capacity goes to TRUE 0% and not 0% showed on your screen.
2) You can charge your phone to 100% everytime and you can leave it over night plugged at 100% for the whole night. Charging to 100% of what BMS allows doesn't harm your battery AT ALL. In fact number of charging cycles for li-ion batteries is based on DOD which is Depth of discharge e.g. >1000 cycles @ 100% DOD, >2000 cycles @ 90% DOD etc. Depends on a paricular lithium battery, manufacturer etc. And as to leaving phone connected to charger when it's already 100% does NOTHING because BMS disconnects the charger itself, you don't have to do it by unplugging the battery. Lithium battery has to be controled this way or else it blows up (literally). When you have 100% battery and your phone is still connected to the charger, battery is on stand by and your phone use power from charger only. That's why you'll always have 100% battery while plugged.
3) The moment BMS decides to end charging is usually when current reaches so called CUT OFF value which means battery can no longer take current that is more than e.g 150mA so when your phones charges <150mA for a set period of time, BMS knows it's fully charged and it has to be disconnect or else the voltage can rapidly increase, overloads battery and cause the damage, usually blow-up.
4) The process of charging li-ion batt goes like this (let's start from full current):
a) CC (constant current) stage which means the battery takes full current, in this case 4A but frankly it's 3,4-3,6A.
For 3,3Ah battery it's current around 1,1C, it's perfectly good value for battery life.
b) when battery reaches certain point of voltage (on Dash I noticed it's around 60-70% approx.), current drops naturally and it keeps going down with increasing voltage
c) CV (constant voltage) means BMS sets 4,2V (usual value for 100% capacity of lithium cell) and current is going to 0A since your battery is almost charged at this point e.g 4,1V and charger gives 4,2V which is 4,2-4,1V = 0,1V, it allows really low current. But it's important to charge to 100% because last stage lasts long but it gives you significantly more capacity, especially for only 3,3Ah cell. Moreover, this stage is most dangerous because voltage for almost fully charged cell becomes unstable and when it takes current, it'll increase voltage easily and rapidly. That's why cut off current has to work and stops charging when it's time. The process can go a few times e.g. if battery goes >4,2V, the charger disconnects, waits few seconds, lower current from charger and starts charging again. And after e.g. 3 repeates, it ends the charging process for good.
5) In a nutshell, don't let your battery discharge lower than 10% and it'll keep capacity longer. That's kind of additional way to enhance battery life because BMS itself will never let your battery to discharge to 0% capacity. They can't allow it because number of cycles would be too low and capacity would drop too fast. You can charge to 100% everytime and keep it through the night, it'll do no harm at all. And if you can, you use your phone connected to the charger when battery's full. That way you don't use your battery at all.
Greetings
1) Discharging to 0% and charging to 100% as a "calibration" is pure bullshit. Does nothing good for your battery and only harms it because li-ion batteries doesn't "like" to be discharged to low capacity. I wouldn't say 0% capacity because battery management system probably turns of the phone before capacity goes to TRUE 0% and not 0% showed on your screen.
2) You can charge your phone to 100% everytime and you can leave it over night plugged at 100% for the whole night. Charging to 100% of what BMS allows doesn't harm your battery AT ALL. In fact number of charging cycles for li-ion batteries is based on DOD which is Depth of discharge e.g. >1000 cycles @ 100% DOD, >2000 cycles @ 90% DOD etc. Depends on a paricular lithium battery, manufacturer etc. And as to leaving phone connected to charger when it's already 100% does NOTHING because BMS disconnects the charger itself, you don't have to do it by unplugging the battery. Lithium battery has to be controled this way or else it blows up (literally). When you have 100% battery and your phone is still connected to the charger, battery is on stand by and your phone use power from charger only. That's why you'll always have 100% battery while plugged.
3) The moment BMS decides to end charging is usually when current reaches so called CUT OFF value which means battery can no longer take current that is more than e.g 150mA so when your phones charges <150mA for a set period of time, BMS knows it's fully charged and it has to be disconnect or else the voltage can rapidly increase, overloads battery and cause the damage, usually blow-up.
4) The process of charging li-ion batt goes like this (let's start from full current):
a) CC (constant current) stage which means the battery takes full current, in this case 4A but frankly it's 3,4-3,6A.
For 3,3Ah battery it's current around 1,1C, it's perfectly good value for battery life.
b) when battery reaches certain point of voltage (on Dash I noticed it's around 60-70% approx.), current drops naturally and it keeps going down with increasing voltage
c) CV (constant voltage) means BMS sets 4,2V (usual value for 100% capacity of lithium cell) and current is going to 0A since your battery is almost charged at this point e.g 4,1V and charger gives 4,2V which is 4,2-4,1V = 0,1V, it allows really low current. But it's important to charge to 100% because last stage lasts long but it gives you significantly more capacity, especially for only 3,3Ah cell. Moreover, this stage is most dangerous because voltage for almost fully charged cell becomes unstable and when it takes current, it'll increase voltage easily and rapidly. That's why cut off current has to work and stops charging when it's time. The process can go a few times e.g. if battery goes >4,2V, the charger disconnects, waits few seconds, lower current from charger and starts charging again. And after e.g. 3 repeates, it ends the charging process for good.
5) In a nutshell, don't let your battery discharge lower than 10% and it'll keep capacity longer. That's kind of additional way to enhance battery life because BMS itself will never let your battery to discharge to 0% capacity. They can't allow it because number of cycles would be too low and capacity would drop too fast. You can charge to 100% everytime and keep it through the night, it'll do no harm at all. And if you can, you use your phone connected to the charger when battery's full. That way you don't use your battery at all.
Greetings
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