Battery Indicator Light Turns On and Off While Battery is Charging
If the battery charge LED indicator light turns on and off while AC power is connected and the battery is still charging, the battery is simply in a low-charge state. The Windows battery property shows that the battery is Online - discharging . This occurs because of the battery's charging cycle.
HP Notebook PCs use lithium ion (Li-ion) batteries. Li-ion batteries are charged using a fast charge/slow charge charging cycle—meaning that the battery is continuously infused with a lot of power (fast charge) and then with very little power (slow charge). During the slow charge stage of the cycle, the battery indicator light may turn off and appear as though it is not charging.
Understanding the battery LED status
The battery LED on some notebooks does not operate as stated in the manual. The correct operation is as follows:
Notebooks with a dual color battery charge indicator:
LED status Battery charge status
AMBER 0% to 99% Charge
GREEN 100% Charge
OFF No battery inserted or power has been removed and re-applied.
Notebooks with a single color battery charge indicator:
LED status Battery charge status
ON 0% to 99% Charge
OFF No battery inserted or power has been removed and re-applied.
If power is removed and then re-applied while the battery is at or above 95%, the battery charge LED will not illuminate.
The battery charge LED will only illuminate if the battery is between 0 and 94% when power is applied.
In order to reduce the number of short charge cycles and extend the service life of the battery, the notebook is designed to initiate charge only when the battery capacity is below 95%. Therefore, even though an AC adapter is connected to the system, the battery will not charge if its capacity is 95% or greater.
If the adapter is plugged into the notebook and the battery capacity is 95% or greater, the charge LED will not light until the battery begins to charge.
This may take several days since there is no drain on the battery while the notebook is running on AC power.
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