Our company just get 30% investment from the best Lithium battery manufacturer. So that we will self-confidently claim 8 years warranty or 50000kms on battery if you buy our high performance electric scooter equipment with CHL lithium battery and Active BMS. This would be the world record in field of EV. CHL lithium battery are set up in 2010 target for Kinglong E-bus supply and we use high performance materials which could bear 6C constant discharged current and temperature are never raised more than 10 degree during discharging because of 0.16m??(ohm) low impedance. Our life cycle testing with 1c charged and discharged is around 1916cycle with only 30% capacity reduced,so that 8 years with 400 deep cycle charging every year would be definitely not problem.see attached data. Active BMS would be another revolution in field of EV,our active BMS uses electromagnetism inductance principle for moving excessive charge of one cell to nearby not so full cell. This can work both during charging as well as discharging, and only limited to 1A or 2A small currents. The system is called active BMS or inductive BMS that uses cable to transfer higher currents between cells, in contrast to the usual "passive PCM balancers" who just simple "burn off" excessive charge of cells by heat resistance. Which might cause potential fire incident too. Active BMS should yield higher efficiency than passive systems because the energy is mostly retained instead of consumed as heat, and could thus also allow slightly higher vehicle range. You may get reference from EVhttp://visforvoltage.org/forum/11326-erider-8000w-scooter-australia-similar-xm5000li Seeing is beliving,customer feeback would be the best proof of my scooter and battery, http://youtu.be/-qTirMorn5w http://youtu.be/tjbION8Ey1A http://www.youtube.com/watch?v=O1p8Mn2QtqU http://www.youtube.com/watch?v=Ypb_gXAUiC0 or http://www.youtube.com/watch?v=hQjrCz5byiQ