Simple battery life simulator
To help you, we have added a simple Excel sheet which calculates estimated battery life. For the calculation, you need to estimate behaviour of your Purpose.
Using the guidance from the previous articles, give estimates for the key components:
- What is the average running interval of the component (in seconds, minutes, hours or days, one figure only).
- What is the average current used by average single run of the component
Last group in the Excel is sleeping power consumption. For sleeping just put 1 if the component is active during sleeping and 0 if inactive. In most cases changes in the sleeping current consumption do not have a big effect to the battery life. Sleeping power is important in the very long battery life applications.
Actual battery life depends on very many things, temperature being one of the most important factor. This simple simulator gives you some idea of what the battery life could be but the results need to be checked in real environment. In below zero celcius temperatures battery capacity can drop in a fraction of the normal capacity. You can estimate below zero battery life by changing the capacity in the Excel sheet from 1900 mAh to say 200 mAh.
If the battery life is in a range of months, battery self discharge needs to be taken into account. Self discharge is around 2% of the remaining capacity per month (around 20% per year) but it again depends on temperature. If the simulator shows two years battery life, real battery life can be less than 1.5 years due to self discharge.
NEW SIMULATOR WITH DISCHARGE