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Dual 18650 Lithium Battery Shield Arduino raspberry pi Power Expansion Board Module


5V voltage output rated current is 2.2A, maximum support 3A current (not recommended for overload, easy to damage the module, speed up the service life), the output of current depends on the quality of the 18650 battery
Micro-USB charging current 600-800mA. 
Supports up to two 18650 batteries. It is recommended to use two 18650 batteries, which can be longer
When the switch is turned to NORMAL, the current output is lower than 30mA, and it will stop automatically in about 10 seconds and turn to standby mode
When it is turned to HOLD, it will be turned on in any case until the battery is dead (2512 resistor on the back will heat up)
Special attention: the installation of the battery must be determined positive and negative, the board has been clearly marked positive and negative! Installation errors will burn out the module