Understanding Industrial Robot Power Sources and Supply

Robots are expected to work tireless hours, yielding perfect, precise results around the clock. But what powers them? They don’t need food and water; they need a power source. The selection of a robotic power source should be decision made in the early stages of design since it impacts the complete system.

Battery Options to Power Robots

Batteries are the most widely used power source for robots due to their flexibility and adaptability across various applications. Choosing the right battery is necessary to ensure optimal performance, safety, and efficiency. The type of battery selected depends on the robot's intended use, design constraints, and environmental conditions.

Lead-Acid Batteries

Lead-acid batteries are one of the oldest and most commonly used battery types in robotics. They are known for their affordability and availability, making them a cost-effective choice for many applications.

Lead-acid batteries are inexpensive, easy to source, and reliable for high-power applications. They also have a proven track record and are simple to maintain. However, these batteries are heavy and bulky, making them less suitable for mobile robots. Their relatively short lifespan and sensitivity to deep discharges can also limit long-term use.

Lead-acid batteries are ideal for stationary or semi-mobile robots, such as industrial robotic arms or automated warehouse robots, where weight is not a primary concern.

Lithium-Ion Batteries

Lithium-ion (Li-ion) batteries are the leading choice for powering modern robots. They offer an optimal balance of performance, efficiency, and lightweight design. Due to their high energy density, robots can operate for extended periods without frequent recharging, making them ideal for drones, autonomous vehicles, and mobile robots.

Despite their many advantages, lithium-ion batteries have certain drawbacks. Their higher upfront cost than older battery technologies, like lead-acid or nickel-cadmium, can be a challenge for budget-conscious projects. They also require sophisticated battery management systems (BMS) to ensure safety, as they are prone to overheating, overcharging, or thermal runaway when not properly supervised.

Nevertheless, their versatility and consistent performance make lithium-ion batteries indispensable for industrial and consumer robotics.

Lithium Polymer (LiPo) Batteries

Lithium Polymer (LiPo) batteries are a popular power source for robots because of their lightweight design, high energy density, and flexibility. Unlike traditional lithium-ion batteries, LiPo batteries use a polymer electrolyte, allowing them to be shaped into thin, compact configurations that fit into robotic designs. This makes them well-suited for types of robots with limited space and weight, such as wearable robotics.

Additionally, their ability to deliver high discharge rates provides the power needed for fast and precise movements, making them a preferred choice for agile and performance-focused robots.

Despite their benefits, LiPo batteries are more fragile than other battery types and require careful handling to prevent damage. Overcharging or physical impact can cause swelling, reduced lifespan, or even safety hazards like fire.

Silver-Cadmium Batteries

While less commonly used, silver-cadmium batteries offer unique benefits for specific applications. They are lightweight, durable, and resistant to temperature variations, making them reliable in harsh environments. These qualities make silver-cadmium batteries a strong contender for aerospace or defense robotics, where weight savings and resilience are required.

However, their high cost and the environmental concerns associated with cadmium, a toxic material, limit their widespread adoption and require careful disposal practices.

Primary (Non-Rechargeable) Batteries

Primary batteries, such as alkaline or lithium primary cells, are designed for single-use applications where recharging is not feasible. These batteries deliver high power output and are ideal for situations where consistent, long-lasting energy is required without access to recharging facilities. Unfortunately, once depleted, primary batteries must be replaced, leading to higher costs and environmental waste in the long term.

Primary batteries are commonly used in disposable robots, remote sensors, or robots deployed in remote locations where recharging is impractical or impossible.

Nickel-metal hydride (NiMH) Batteries

NiMH batteries offer a compromise between older technologies like lead-acid batteries and modern options like lithium-ion batteries. These metal hydride batteries are safer and more environmentally friendly than lead-acid and silver-cadmium batteries, and they provide greater energy density than lead-acid options.

These widely available and cost-effective batteries are suitable for robots that require moderate energy output. However, their energy density and lifespan are lower than lithium-ion batteries, leading to shorter operational times and faster degradation with frequent charging cycles.

Solid-state Batteries

Solid-state batteries are an emerging technology with significant potential for robotics. They use solid electrolytes instead of liquid ones, improving safety and performance. Solid-state batteries also have a high energy density and a compact design, making them suitable for advanced robotics, medical devices, and drones.

Their longer lifespan and reduced risk of leakage or thermal runaway make them safer choices. However, they are currently expensive and not widely available for large-scale robotic applications.

Nickel-Cadmium (NiCd) Batteries

Nickel-cadmium (NiCd) batteries are known for their durability and reliability because they perform exceptionally well in extreme temperatures. This makes them particularly useful in environments where other batteries might fail. They also have a long cycle life and can endure frequent charging and discharging without significant degradation, which is ideal for robots that operate in demanding industrial settings or challenging outdoor conditions.

However, NiCd batteries have a significantly lower energy density than lithium-ion or nickel-metal hydride (NiMH) batteries, which means they provide less power for the same weight and size. This can be a drawback for mobile robots or applications where compact, lightweight power sources are essential.

Additionally, cadmium, a key component of these batteries, is highly toxic and poses serious environmental concerns. Proper disposal and recycling practices are necessary to prevent environmental harm, and these processes can be costly and complex.

Zinc-Air Batteries

Zinc-air batteries generate electricity by combining zinc with oxygen from the air. This eliminates the need for a separate oxidizer and allows for a lightweight and compact design. As a result, zinc-air batteries offer one of the highest energy densities among commercially available batteries, making them an appealing option.

Zinc's low cost and relative simplicity make zinc-air batteries an excellent choice for low-power small robots, sensors, and devices used in remote or isolated locations. Their extended runtime and ability to maintain steady energy output over long periods are significant advantages in these scenarios.

Despite their potential, one major drawback is their limited rechargeability. Additionally, these batteries are sensitive to environmental conditions, particularly humidity, which can degrade their performance and reduce their lifespan.

Alternative Energy Sources for Robots

Several alternative power sources are available for robots, each offering unique advantages depending on the application. These options provide solutions for specialized needs, such as high energy efficiency, compact designs, or operation in specific environments.

Thermoelectric Generators

Thermoelectric generators (TEGs) convert heat directly into electricity using the Seebeck effect. They are highly reliable, have no moving parts, and can operate in extreme environments. They are often used when a consistent waste heat source is available, such as industrial robots working near furnaces or engines.

Although TEGs provide a clean and maintenance-free power option, they have a relatively low efficiency compared to other technologies, limiting their use to specific applications.

Fuel Cells

Fuel cells generate electricity through a chemical reaction between a fuel (such as hydrogen) and an oxidant, which is continuously supplied. Unlike traditional batteries, fuel cells do not require recharging. Instead, they operate as long as the fuel supply is maintained, making them an excellent choice for robots requiring long operational times without interruptions.

They are commonly used in autonomous robots, underwater vehicles, and drones. However, fuel cells can be costly, and the infrastructure needed to store and transport fuel adds complexity to their implementation.

Supercapacitors

Supercapacitors store energy as an electric charge, which is built up on plates separated by a dielectric material. They can deliver a high burst of energy quickly, making them suitable for robots that require rapid, short-term power boosts, such as robotic arms or grippers.

They also have a long cycle life and can withstand frequent charging without degradation. However, they have lower energy storage capacity than batteries, which limits their use as a primary power source. Instead, they are often paired with batteries to enhance performance.

Tethers

Tethered power sources connect robots directly to an external power supply through a cable. This eliminates the need for onboard power storage, saving weight and space, which can be especially helpful for lightweight robots or those with limited mobility. Tethered robots are often used in industrial and underwater applications where constant power is needed and mobility is restricted.

However, dependence on a physical connection can be disadvantageous since the tether may restrict movement and pose an entanglement risk, particularly in dynamic or cluttered environments.

Power Products for Robotics

Emerson Network Power makes power supply products for the robotics market. Emerson’s products can be used for automated assembly, manufacturing, and packaging, goods handling and transport, warehouse management, pick-and-place systems, and portal robots. Some of the main attributes of their products include a wide operating temperature range, high efficiency and reliability, and small form factors.

Lincoln Electric developed the Power Wave R350 K3022-1 and the R500 K3169-1 models of a compact multi-process robotic power source. Both sources have built-in wire feeder control and are ideally used in robotic welding applications. Some main features of the Power Wave models are the PowerConnect Technology which automatically adjusts to input power while maintaining a constant output, and the Auxiliary Power Surge Blocker Technology, ensuring performance is not affected by simultaneous use of other devices requiring high current.

Air Liquide Welding assures customers that their new cutting machines equipped with TOPWAVE have many benefits. TOPWAVE combines the performance of DIGIWAVE and CITOWAVE power sources to OTC robotics. A smart teach pendant for both the power source and the OTC robot ensures all-in-one simplified programming.

Find the Right Power Source for Your Robot Today

With so many power source options available, it’s important to carefully evaluate your robot’s unique requirements to ensure optimal functionality. At Robots.com, we specialize in helping businesses and innovators find the perfect power solutions for their robots. Whether you’re integrating industry-leading robots from KUKA, Motoman, ABB, or Fanuc, we provide expert guidance and integration-ready solutions tailored to your needs.

Our team of professionals can help you navigate the complexities of power source selection so your robot is equipped to achieve peak performance. Click here or give us a call at 877−762−6881 to learn more about how to incor­po­rate the right robot pow­er source and take the first step toward maximizing your robot’s potential. r.