The battery capacity of my FP1 isn’t whats it used to be and sometimes I found it empty. In order to make the phone last a little longer I’m thinking on buy an external battery for that occassions where I am not able to plug it.
The most of then (like https://www.amazon.es/gp/product/B01CQWJDZW) have an output power of 2A. Will it be secure use one of this batteries or my FP1 will suffer with them?
The Fairphone will only charge at 1A because that is the highest current it can take. So it will be safe to use the battery back, but charging will take longer than with an iPhone / Samsung / FP2.