.. __Note:

Note
==========================

• Caution 1: When connecting batteries for the first time, check the LED indicator.  
  If the LED lights up, the battery is connected in reverse.  
  Do NOT charge when batteries are reversed.

• Caution 2: The board may not output power on first battery connection.  
  Press the BOOT button on the PCB to activate the battery-protection IC.

• Caution 3: Charge only with the supplied 12.6 V 2 A adapter.  
  Using other chargers may cause excessive ripple or instability and damage the unit.

• Caution 4: Do not use the product if the positive-terminal insulating pad is missing or damaged—risk of short-circuit and fire.  
  When removing batteries, pry from the negative terminal only; never pry the positive end with a screwdriver.

.. warning::

   ⚠️ **Lithium Battery Usage Warnings**

   1. **Fire & Injury Risk**  
      Li-Po/Li-ion cells are highly unstable; improper charging or use can cause fire, personal injury, or property damage.

   2. **Polarity & Charger**  
      Never reverse polarity when charging or discharging.  
      Use only high-quality chargers/charging boards designed for lithium batteries.

   3. **Battery Mixing**  
      Do not mix old and new cells or combine cells from different brands.

   4. **Replacement Batteries**  
      When purchasing new batteries, verify their specifications are compatible with the expansion board.  
      Select reputable manufacturers and perform aging tests to ensure safe, stable operation.

   5. **Cycle Life**  
      Lithium cells have a limited cycle life. Replace them after two years of use or when their rated life is reached, whichever comes first.

   6. **Storage**  
      Store batteries in a secure location, away from flammable or explosive materials and out of reach of children to prevent accidents.