I am very happy with my Crossfire-E that I bought a few months ago. However, I don't know if the battery is defective. Every time I fully charge the battery and go for a 6 miles ride (3 miles to wherever I am going and 3 miles back) the battery drops to around 70 and 75%. Is this normal? I am 18 stone and carry a backpack full of shopping. The journey is slightly uphill but not too steep and I use the sport power assist (cheetah). When going downhill I switch the power assist off and when I am cycling on level ground then it is on city power assist (squirrel). Also, I have noticed when charging at home, the light on the battery charger turns green and when I connect the battery back on to my ebike, the battery percentage reads as 99% instead of 100%. Please advise.