I've noticed that my recharge Bots act a little strange. Many times one will run from across the map to charge a dead Bot when there is a charge bot sitting far closer. This will also trigger other charge Bots to move to the dead Bot if the distance is great. This behavior is also seen in other Bots doing different jobs, ie logging and lumberjacks. Not a huge problem as I use chargers all over my factory, just an observation.