Hot Sell 3.7V 5mAh Smallest Thin Film Cell OTP Card Film Battery, Besides the traditional advantage of Lithium manganese batteries, the thin cells have the following advantages: Good safety: Using soft aluminium foil packaging eliminates the possibility of explosion, and greatly reduces the probability of fire. Small volume: Comparing the same capacity, the volume would be smaller 15% than the batteries with metal shell such as coin cells and cylindrical cells due to the foil packaging used in the thin cells. Light weight: the weight is lighter 40% than cells with metal shells of the same capacity. High capacity: Comparing volume, the capacity is higher 10% than batteries with metal shells. Higher discharge current and discharge level: the battery is vacuum packed, so atmospheric pressure forces the anode and cathode foils together. 3C discharge rate is possible for specially designed cells. Wide range of temperatures: can be used under -40~75 °C (-40 to 167 °F). Low self-discharge: The rate of self-discharge per year is smaller than 2%. Flexibility in shape & size: this technology allows custom cells to be made with low-cost tooling.