Optimizing Battery Packs for Mobile Industrial Robots in Hazardous Environments
Part 1: Ensuring Efficiency and Safety
In the realm of mobile industrial robots, achieving long cycle life, high energy density, and resistance to shocks and vibrations are crucial factors when designing battery packs. How do these requirements influence the choice of battery chemistry, cell, and pack design? This article explores these considerations, with a special focus on applications in hazardous environments where safety is paramount.
Efficiency and Safety in Modern Industrial Automation
Efficiency, maximizing throughput, safety, and reducing operating costs are the pillars of today’s advanced, digitalized factories and warehouses. To achieve these objectives, industrial companies are increasingly automating processes and deploying more mobile robots, including automated guided vehicles (AGVs) for material handling and automated mobile robots (AMRs) for last-mile deliveries.
A significant advantage of mobile robots over human workers is their ability to operate 24/7 without breaks. This necessitates a portable battery power system that can deliver continuous output without running out of charge or failing prematurely. Additionally, robots can perform repetitive and dangerous tasks that are either impossible or too risky for humans. They are adept at working in confined spaces and extreme environments, such as those with high temperatures, toxic substances, or explosive atmospheres, where human safety would be compromised. This underscores the importance of specifying the right battery pack for mobile robots. Typically, a custom pack is required to meet the application’s unique needs for capacity, size, ruggedness, peak power output, cycle life, temperature tolerance, and more. Choosing the right custom battery pack manufacturer is therefore critical.
Applications Requiring Intrinsic Safety
Intrinsic safety is critical in environments where there is a risk of explosion due to flammable gases, vapors, or dust. Examples of industries where intrinsically safe battery packs are essential include:
Oil and Gas
In oil refineries and offshore drilling rigs, where flammable gases are present, battery packs must be designed to prevent sparks or excessive heat that could cause explosions.
Mining
Underground mines often contain flammable gases like methane, requiring battery packs that can operate safely without igniting these gases.
Chemical Manufacturing
Facilities that produce or handle volatile chemicals need battery packs that are robust against potential ignition sources.
Pharmaceutical Production
Certain pharmaceutical processes involve flammable solvents, making intrinsically safe battery packs necessary to ensure safe operation of robotic units.
Grain Handling and Processing
Dust from grains can be highly explosive, requiring battery packs that prevent dust ignition in processing plants and storage facilities.
Choosing the Right Battery Chemistry for Intrinsic Safety
Lithium-based batteries are the predominant choice in new industrial applications due to their high energy density and capacity, offering significantly longer run-times between charges compared to other battery types. Various lithium chemistries, such as lithium nickel manganese cobalt oxide (NMC), lithium iron phosphate (LFP), lithium titanate (LTO), lithium manganese oxide (LMO), and lithium cobalt oxide (LCO), are used in battery cells. The technology and production of these battery packs are continually advancing, providing OEMs with better specifications each year.
When considering intrinsic safety, the choice of battery chemistry is crucial:
- NMC (Lithium Nickel Manganese Cobalt Oxide): Offers high energy density, making it suitable for compact applications. However, it has a lower thermal stability compared to other chemistries, which can be a concern in hazardous environments.
- LFP (Lithium Iron Phosphate): Known for its excellent thermal stability and long cycle life, making it a preferred choice for applications where safety is critical. LFP cells can operate safely at higher temperatures and are less prone to thermal runaway, a key advantage in explosive atmospheres.
- LTO (Lithium Titanate): Provides exceptional cycle life and fast charging capabilities, with very stable chemistry. Its lower energy density can be a drawback for compact applications, but its safety profile makes it ideal for hazardous environments.
- LMO (Lithium Manganese Oxide) and LCO (Lithium Cobalt Oxide): These chemistries offer good performance but have limitations in terms of thermal stability and cycle life compared to LFP and LTO, making them less ideal for intrinsically safe applications.
- LCB (Lithium Ceramic Battery): The latest advancements in solid-state battery technology provide the safest solution while maintaining the high energy density of the battery cells. While the price of these solutions is typically 7 times higher, our customers benefit from the lightweight mobile battery solutions since 2018, which is still a unique offer on the worldwide market.
Choosing the right battery chemistry is not only about meeting the energy and performance needs but also ensuring safety in hazardous environments. Custom battery packs designed with the appropriate chemistry can significantly enhance the reliability and safety of mobile robots operating in such challenging conditions.
In this first part, we have outlined the importance of efficiency and safety in modern industrial automation and highlighted the key applications that require intrinsically safe battery packs. We have also discussed the critical role of choosing the right battery chemistry for these challenging environments.
