The perfect battery would have a curve that is horizontal and first right at the end goes down. Conrad Electronic UK announced a volume discount for bulk orders of our ever popular Conrad Energy lithium battery button cell.
The limiting factor is battery capacity depends how long they can give. But how do you know how long a battery lasts?
To calculate how long battery life, you must first know what the capacity of the battery. This capacity is indicated on the battery in mAh or Ah. This stands for (milli) amperes per hour.
A battery with a capacity of 2400 mAh can deliver 2400mAh example 1 hour, or 2 hours 1200 mAh, 600 mAh or 4 hours and so on.
In addition to this capacity is also the discharge curve of interest. This curve varies by battery and is often found in the datasheet or the Internet.
The perfect battery would have a curve that is horizontal and first right at the end goes down. Although this type of battery does not exist, there will be more self-discharge batteries that barely, like the latest NiMH batteries. An example of such a "low self-discharge" battery, the eneloop series of Sanyo.
In addition to the self-discharge and the discharge of its use, there are other factors which affect the service life of the battery. For example, the voltage of the device in which the battery is used, and also of importance to the ambient temperature plays a role: the higher the temperature, the shorter the life of the battery. Capacity Calculation
In 1897, Mr.. Peukert has developed a formula by which the relationship between capacity and discharge can be calculated fairly accurately.
This formula is as follows:
T = C / In
Here T the time in hours, C is the theoretical capacity in Ah, I the current and N is the Peukert number (this number is often between 1.1 and 1.3, depending on how well a battery against discharge can).