My auto-answer: 
https://www.thethingsnetwork.org/forum/t/big-esp32-sx127x-topic-part-1/10247/38
Onboard lithium battery charge and discharge circuit, The orange LED lights will go out when the battery is full , only provide the basic lithium battery charging and discharge function, can not monitor the battery temperature and power, if your battery is not purchased in our shop, Please pay attention to the battery positive and negative, wrong operation may explode.