Buy SparkFun Pro nRF52840 Mini - Bluetooth Development Board Includes LiPo battery charger Qwiic connector Onoff switch Reset switch User LEDbutton Pre-programmed with a USB bootloader Small footprint Online in Italy. B07MWGN5KV
LiPoly Fast Charger - 5-12V Input
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Sparkfun PRT-10473 Li-Ion/Polymer Battery Charger/Balancer - 80W, 5A Arduino, Electronics and Robotics Electan, OnLine Store
SparkFun Sunny Buddy - MPPT Solar Charger
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PRT-15217 SparkFun Electronics | Development Boards, Kits, Programmers | DigiKey