The conversion of 900 mah to wh equals 0.81 wh.
This is calculated using the formula: wh = mah × voltage / 1000. Assuming a standard voltage of 0.9V for typical lithium-ion batteries, multiplying 900 mah by 0.9V and dividing by 1000 gives the watt-hours. So, 900 × 0.9 / 1000 = 0.81 wh.
Understanding the Conversion
To convert milliampere-hours (mah) to watt-hours (wh), the key is knowing the voltage of the battery. The formula involves multiplying the capacity in mah by the voltage in volts and then dividing by 1000. This process transforms charge capacity into energy content, measured in watt-hours. For example, a 900 mah battery at 0.9 volts: 900 × 0.9 / 1000 = 0.81 wh. This reflects the energy stored in the battery, useful for comparing power across different devices and battery types.
Conversion Tool
Result in wh:
Conversion Formula
The formula to convert mah to wh is: wh = mah × voltage / 1000. It works because mah measures the charge capacity, and voltage determines how much energy each unit of charge holds. Multiplying mah by voltage gives the energy in milliwatt-hours, then dividing by 1000 converts to watt-hours. For example, for 900 mah at 0.9V: 900 × 0.9 / 1000 = 0.81 wh.
Conversion Example
- Convert 1500 mah at 3.7V:
- Multiply 1500 mah by 3.7V: 1500 × 3.7 = 5550 mWh
- Divide by 1000: 5550 / 1000 = 5.55 wh
- Convert 500 mah at 1.2V:
- 500 × 1.2 = 600 mWh
- 600 / 1000 = 0.6 wh
- Convert 2000 mah at 3.6V:
- 2000 × 3.6 = 7200 mWh
- 7200 / 1000 = 7.2 wh
- Convert 100 mah at 3.7V:
- 100 × 3.7 = 370 mWh
- 370 / 1000 = 0.37 wh
- Convert 900 mah at 0.9V (original example):
- 900 × 0.9 = 810 mWh
- 810 / 1000 = 0.81 wh
Conversion Chart
| mah | wh |
|---|---|
| 875.0 | 0.7875 |
| 880.0 | 0.792 |
| 885.0 | 0.7965 |
| 890.0 | 0.801 |
| 895.0 | 0.8055 |
| 900.0 | 0.81 |
| 905.0 | 0.8145 |
| 910.0 | 0.819 |
| 915.0 | 0.8235 |
| 920.0 | 0.828 |
| 925.0 | 0.8325 |
This chart helps you quickly find the watt-hour equivalent for mah values from 875 to 925, assuming a voltage of 0.9V. To use, locate your mah value in the first column and read across to find the corresponding wh in the second column.
Related Conversion Questions
- How many watt-hours is 900 mah at different voltages?
- What is the energy content of a 900 mah battery with a voltage of 1.5V?
- Can I compare batteries with capacities in mah and wh directly?
- What voltage should I assume for standard lithium-ion batteries when converting mah to wh?
- How does changing the voltage affect the watt-hour calculation for 900 mah?
- What is the difference between mah and wh in terms of battery capacity?
- How do I convert mah to wh if the battery’s voltage is unknown?
Conversion Definitions
mah
Mah (milliampere-hour) is a measure of electric charge representing the amount of current a battery can deliver over one hour. It indicates capacity but does not directly measure energy content, which depends on voltage.
wh
Wh (watt-hour) is a unit of energy measuring the total amount of work a battery can perform, calculated by multiplying capacity in amp-hours by voltage. It shows how much energy the battery stores and can supply over time.
Conversion FAQs
How accurate is the conversion from mah to wh?
The accuracy depends on knowing the exact voltage of the battery. Using an assumed voltage like 0.9V provides an estimate, but actual energy content varies with the real voltage. For precise calculations, always use the specific voltage of your battery.
Why does the watt-hour value change with different voltages?
Because wh depends directly on voltage; higher voltage batteries store more energy per unit charge. For example, a 900 mah battery at 1.2V has more wh than at 0.9V, reflecting the increased energy capacity due to higher voltage.
Can I convert mah to wh for all types of batteries?
Yes, but only if you know the voltage of the specific battery. Different battery chemistries and types have different voltages, so using the correct voltage is crucial for accurate conversion from mah to wh.