How to perform deep discharge? Is deep discharge useful?
Last week , a friend shows me the problem ,he used the battery for 3 months ,now the battery is not working good ,it is a Dell XPS 15 9570 (2018) laptop, When plugged the battery in, it had 87kWh as its maximum charge, which is already 10kWh lower than what it design. The more concerning thing is the rate at which the capacity falls. It is less than a month later and there is a further 10kWh decrease. It has dropped to less than 77kWh. All of this is happening with very mild usage of the laptop. If this trend continues, it is unacceptable for it to lose close to 25%; this directly affects the battery’s performance. It used to last for 3 hours, but now it may only support 1.5–2 hours, which reduces the ability of the notebook to work outdoors. Could it be that such a battery is not saved?
Firstly, I need to explain two concepts:
1. The normal cycle of deep discharge is many times.
It is mainly our usual electricity usage habits. If each time is overcharged and over-discharged, the internal materials of the cell will decompose, which making the cell in a very unstable state, which will seriously affect the life of the cell.
2. The capacity recovery method involves a small amount of deep discharge.
When we need to restored the capacity, deep charge and discharge are required. After a certain cycle, deep charge and deep discharge are required to realize the capacity reduction of some lithium ions because they fail to participate in the reaction at a high rate. It is generally implemented after a certain number of cycles.
The capacity recovery method is as follows: First, start the laptop to enter the system, unplug the external power supply, use the battery to supply power, and automatically shut down until the battery is exhausted. Then, plug in the power supply to charge and turn it on until it is fully charged, then unplug the external power supply again, and automatically shut down until the battery is exhausted. Repeat the operation more than 3 times to repair the battery, and the capacity of the battery can be restored to a certain extent.
HP notebook laptop :how to care for and store the battery
Recharge after the battery is exhausted
Regardless of whether the notebook uses lithium or nickel metal hydride batteries, be sure to recharge after the battery is used up (the battery is less than 1%). This is the best way to avoid the memory effect. Only charge the battery after the battery is completely used up. Part of the charge and discharge may cause the chemical properties of the cells in the battery to be inconsistent, and thus the battery performance will be reduced.
It is recommended that the battery be deeply discharged every few months to optimize battery performance.
The specific method is: Disable the power management function of the operating system and BIOS, use battery power, and use it until the system shuts down. Then connect the AC charger until it is fully charged. Then restore the BIOS and operating system power management settings.
