One of the most crucial elements that is used in the batteries of most pieces of tech is cobalt, a metal that is usually mined out of Africa, specifically, the Democratic Republic of Congo. In and of itself, cobalt mining is a nasty business and causes a lot of environmental damage. However, what’s worse about cobalt mining is that it disproportionately involves child labour. As a result, all tech companies who source their cobalt from Congo, have been accused of using child labour in some form or the other. This includes Apple. Apple revealed plans on Thursday to build batteries…