Choosing the Right AMR Battery
When it comes to selecting the optimum battery for an AMR (autonomous mobile robot) system, there are many factors to consider. Those include base current, pulse currents, cut-off voltage, temperature and environmental conditions.
Lithium-ion batteries are also compatible with intelligent telematics systems that can send data about the battery, its power usage and how much time remains before it’s fully charged. This enables the AGV/AMR software system to know when it needs to spend downtime in the charger, maximizing uptime and efficiency.
Long Lifespan
Battery life is a key factor when designing an AMR device, especially in wireless applications. The right battery chemistry and battery management system (BMS) can make a huge difference to the operation and durability of an AMR device.
The most important factor in determining battery lifespan is the annual self-discharge rate, which varies depending on the chemistry of the cell and other factors. This is one reason why many theoretical methods for predicting battery life typically under-represent the effects of passivation and long-term exposure to extreme temperatures.
A high self-discharge rate can shorten battery life by reducing the amount of energy available when it is most needed. In addition, a high self-discharge rate can impair performance by limiting the flow of current and increasing the time it takes for the cell to recharge.
In the utility metering industry, Tadiran provides ultra-long-life batteries to power mechanical and ultrasonic meters designed to last as long as the meter without the need for expensive battery replacement. This solution enables utility managers to improve their return on investment by reducing the total cost of ownership while increasing system reliability.
Bobbin-type LiSOCL2 batteries are an excellent choice for AMR devices due to their high energy density, high capacity and wide temperature range. These lithium cells also feature exceptionally low self-discharge, enabling them to operate for up to 40 years.
The key to battery life is managing the annual self-discharge rate and controlling the chemical reactions that reduce energy capacity over time, a process known as passivation. The amount of passivation a battery experiences depends on several factors, including the cell’s capacity and current discharge potential, the fluid/chemistry used to produce it and the prior discharge conditions.
Because of the low self-discharge rates that LiSOCL2 batteries offer, they can be charged more frequently than other lead-acid or nickel-metal hydride cells. For example, a lead-acid battery might require up to 10 hours to charge while a Li-ion battery can reach full strength in less than 15 minutes.
Choosing the right bobbin-type LiSOCL2 battery is a critical design decision for long-life reliability and cost effectiveness. It is important to select a lithium thionyl chloride cell that offers the highest overall capacity while also delivering a minimal annual self-discharge rate, as this will ensure maximum battery operating life over the entire product life cycle.
Fast Charging
AMR batteries can be charged to full strength in minutes. This is a huge advantage for mobile robots, which need to spend most of their time moving through production AMR Battery processes and warehouses. With intelligent battery management systems, they can identify and communicate gaps in their workflow so they can be spent on opportunity charging in the nearest charger.
Fast charging is possible because of the high energy density of lithium ion batteries, which enable the rapid transfer of power. In addition, these batteries do not produce any dangerous hydrogen gas that would contaminate air, making them safe for use in industrial environments.
The XCEL team is working to develop fast-charging electrolytes and advanced electrode designs that are optimized for lithium transport. These improvements are necessary to meet the U.S. Advanced Battery Consortium goals of 80% charge in 15 minutes, 275 watt-hours per kilogram cells, and 1000-cycle lifetimes.
Among these advances is a laser-structured graphite anode that significantly reduces the cell impedance, allowing fast-charging at low charge currents of up to 0.1C. This can be achieved by forming anode structures using short laser pulses (150 ps).
This new approach also allows the application of low-temperature fast-charging processes. The laser structuring is especially beneficial for charging at C-rates of 0.1C and 2C, as the voltage relaxation is much more significant in structured than unstructured cells.
Furthermore, this technique can be applied for a wide range of batteries. It can significantly improve charging time, charging efficiency and rising temperature of the battery.
Another important feature for Li-ion is the ability to support intelligent features, which can monitor the battery’s health and send data to the AGV/AMR software system to help optimize job site performance. This can be accomplished by recording temperature, amp hours of usage, state of charge and more to provide valuable information to the operator.
The XCEL team is working to enhance the lithium transport capabilities of lithium-ion batteries with the use of new electrolytes, advanced electrodes, adaptive electrochemical protocols and optimal thermal controls. This can enable batteries with a faster charge rate, longer calendar life and more machine-learned health adaptivity than conventional lithium-ion batteries.
High Efficiency
AMR battery efficiency is a critical factor to consider when designing an AMR system. Several factors can affect the battery’s performance, including charge current, internal resistance, temperature, and age. Choosing the right battery can help ensure the AMR’s long operating life and safety.
Lithium-ion batteries are a popular choice for AMRs and AGVs due to their low maintenance requirements, durability, and long lifespan. They are also environmentally friendly, reducing waste and helping to reduce carbon emissions.
These batteries are made from the lightweight metal lithium, which has a high specific capacity and unique electrochemical properties. Its combination with manganese dioxide powder, polycarbon monofluoride, or low freezing point liquid cathode materials, such as thionyl chloride or sulphur dioxide, produces primary cells with high energy, high power density, reduced self-discharge, and the ability to operate under extreme temperatures (-40°C to +95°C).
When selecting a battery, it’s important to look at how many hours the device will be used per day and the ambient operating temperature. For example, meters installed outside can AMR Battery routinely experience temperatures ranging from -30°C to +50°C, while a meter fixed inside a utility room could be subjected to a more constant temperature of 50°C.
Using this information, the manufacturer can design a battery that is ideal for your application and use. For instance, if the AMR is designed to work in areas with a high humidity, a rechargeable lithium-ion battery that can handle water may be the best choice.
Another consideration is the battery’s weight, which can impact battery durability and safety. The lighter the battery, the more efficient it will be at charging and discharging.
If the battery is too heavy, it can break or fall over, causing damage and potential injuries to operators. Having the option to switch to a different battery if necessary can help ensure the AMR’s safety and reliability.
A battery management system (BMS) is a vital component of an AMR’s safety and performance. It monitors the AMR’s battery health, records useful data points, and communicates that information to the operator.
The BMS is able to detect when the battery is close to depleting, and it can alert the user to change its battery before it completely loses capacity. A good BMS will also perform auto-balancing of the battery to prevent battery degradation and increase the lifespan of the battery. This helps the battery last longer and perform better, giving users a more cost-effective solution that is safe for operators and customers alike.
Low Maintenance
The AMR battery is a high-performance, low-maintenance power source that delivers the best of both worlds. Its small size, lightweight construction and low maintenance requirements make it the perfect choice for a wide range of material handling applications, from industrial trucks to lift trucks and material transfer vehicles.
An AMR battery is comprised of a combination of plates and separators suspended in a liquid electrolyte. This combination provides a large amount of energy and a long life. It also requires less maintenance than its lead acid counterpart.
Lithium thionyl chloride batteries are one of the most commonly used AMR batteries, offering numerous benefits for manufacturers and utility customers alike. These include high energy density, long life, and the ability to support sophisticated technology like remote power-on and off, meter reading, tank level monitoring, leak detection and more.
In the utility space, lithium thionyl chloride batteries are often combined with a unique Hybrid Layer Capacitor (HLC) to provide power to devices that generate high current surges at periodic intervals. This innovation helps ensure the system-wide reliability of advanced AMR meter designs.
A hybrid battery pack that combines a Tadiran PulsePlus bobbin-type lithium thionyl chloride C-size cell with an innovative Hybrid Layer Capacitor is a big step forward in terms of power efficiency. It also offers a few other notable performance features, including a state-of-charge indicator, diagnostic trouble codes and a battery buzzer that tells you when the battery is about to run dry.
Another feature that is not to be missed is the battery’s built-in, temperature-compensated hydrometer. It measures the quantity of electrolyte and displays it in various colours. This is a very effective way to alert you to any potential problems with the battery.