When you receive your battery, it may have a low state of charge (SOC) due to transportation and storage. To ensure optimal performance, charge the battery immediately to avoid over-discharge.
Batteries with Bluetooth functionality may arrive in an off state, showing a terminal voltage between 3V and 5V, and you won't be able to connect them to your phone. This is because they are shipped powered off, similar to mobile phones, to minimize self-discharge and extend the battery's lifespan.
There are 2 ways to solve the problem: using an AC-DC lithium battery charger or an MPPT solar charge controller to charge it for 3 to 10 seconds, then the battery can be used normally.
If you plan to store the battery for a long time, charge it to a SOC of 50% and perform maintenance every three months. This will help preserve its functionality and performance.