A killer feature that can be replaced by a 6€ external module? https://www.ebay.com/itm/402641596500 https://www.ebay.com/itm/402641596500 (you can get crappi

A killer feature that can be replaced by a 6€ external module? https://www.ebay.com/itm/402641596500 https://www.ebay.com/itm/402641596500 (you can get crappier ones for 2€... this one has a charge controller [MCP73833] from a recognizable brand [Microchip] with datasheets available)