Making robots go!

Everything you need to know about powering your robot

Power Options

There are several ways to power a robot. One option is to use a battery, such as a lithium-ion battery, which can provide a reliable source of power. Other options include using solar cells to capture energy from the sun, or using a fuel cell to convert chemical energy into electricity. Finally, you could also use a combination of sources, such as solar power supplemented with a battery. No matter which source you choose, it is important to make sure your robot is adequately powered for its needs.

Battery power is described in terms of voltage (V), and amps (A), or milliamps, and the capactity of a battery is often described in the number of milliamp hours it will run for at a specific voltage (mAh).

USB Powerbank

USB PowerBanks are enclosed battery with a USB connector (or multiple connectors), often with leds to indicate the remaining charge capacity.

They are a simple and popular choice for robot projects as they:

Li-ion & LiPo Batteries

There are several types of batteries that are used to power robots. The most popular options include lithium-ion, nickel-metal hydride, lead-acid, and nickel-cadmium batteries.


Lithium-ion batteries are a popular choice due to their light weight, high energy density, and long lifespan. They are also relatively low maintenance and easy to recharge. The downside is that they can be expensive, and their performance can be affected by extreme temperatures.


Lithium-ion (Li-ion) and Lithium-polymer (Li-po) batteries are both commonly used in consumer electronic devices like laptops, cell phones, and tablets, but there are many key differences between them. Li-ion batteries are made from a combination of lithium, cobalt, and other materials, while Li-po batteries are made from a combination of lithium, polymers, and other materials. Li-ion batteries are known for their high energy density, low self-discharge rate, and low maintenance requirements, but they are more expensive than Li-po batteries. On the other hand, Li-po batteries are lightweight and more flexible than Li-ion batteries, making them ideal for use in products like wearable technology. However, Li-po batteries have a shorter lifespan and require more frequent charging. Ultimately, which type of battery is right for you depends on your budget, the device you’re using, and the desired performance.


One of the most common type of LiPo battery is the 18650. These are found in electric cars, e-cigarettes, Vape-pens as well laptops and other consumer electronics. The smaller sibling of the 18650 is the 18350. The 18650 gets it’s name from its dimensions; its 18mm in diameter and 65mm long. An 18350 cell means it’s 18mm in diameter and 35mm long. Both come in a variety of capacities, the larger to number the longer it will last.

Nickel-metal hydride

Nickel-metal hydride batteries are another popular option for robots. They are long-lasting, require minimal maintenance, and are relatively inexpensive. However, they are heavier and have a lower energy density than lithium-ion batteries.


Lead-acid batteries are an older technology, but they are still popular for robots due to their relatively low cost and good performance in cold temperatures. On the downside, they are heavy, have a short lifespan, and require frequent maintenance.


Nickel-cadmium batteries are also used in some robots. They have a long lifespan and good performance in cold temperatures. However, they are heavier than other types of batteries and require special precautions for disposal due to their toxicity.

Alkaline Batteries

Alkaline batteries are an excellent source of power for robots. They are reliable, long-lasting, and provide a consistent level of energy. Alkaline batteries are non-rechargable, and are generally cheaper as a one-off cost. However, once they have been fully used up and the battery is flat, they will need to be replaced (and disposed of properly), which means they are a sub-optimal choice for projects projects.


Pros of powering a robot with solar power

  1. is a renewable, clean energy source that produces no emissions or pollutants
  2. is available in most places, making it a convenient and accessible power source
  3. is cost-effective, as the cost of solar panels and other equipment has decreased significantly in recent years
  4. is reliable and can be used in many different types of robots

Cons of powering a robot with solar power

  1. can be affected by weather and other environmental conditions
  2. requires a significant amount of time and resources to set up and maintain
  3. can be unreliable in some locations due to lack of sunlight
  4. can be expensive, depending on the size and complexity of the robot

How to calculate the amount of power a robot will

Calculating the amount of power a robot will need to determine the correct battery capacity can be a complex process. It will depend on the type of robot, its intended use and the environment in which it will be operating. Generally, you need to consider the power requirements of the actuators (motors, servos, etc.), sensors and controllers as well as any other associated electronics. You should then factor in a margin to cover any additional power needs. Once you have determined the total power requirement, you can then choose a battery with a capacity that exceeds the calculated power requirement.

Did you find this content useful?

If you found this high quality content useful please consider supporting my work, so I can continue to create more content for you.

I give away all my content for free: Weekly video content on YouTube, 3d Printable designs, Programs and Code, Reviews and Project write-ups, but 98% of visitors don't give back, they simply read/watch, download and go. If everyone who reads or watches my content, who likes it, helps fund it just a little, my future would be more secure for years to come. A price of a cup of coffee is all I ask.

There are a couple of ways you can support my work financially:

If you can't afford to provide any financial support, you can also help me grow my influence by doing the following:

Thank you again for your support and helping me grow my hobby into a business I can sustain.
- Kevin McAleer