How can we choose the optimum battery for an autonomous underwater vehicle with 8 thrusters on it? We will use pixhawk and raspberry pi 3b on it to work with ardusub. We are very confused about how much power we will need for our drone. It is going to be approximately 8 kg(+ or - 1kg). As I mentioned we will use 8 thrusters. Can anybody help? We will use 860KV T60 thrusters.