Supercharge Your Battery-Powered IoT Devices
IoT Devices Today: More Electronics, More Sensors, More Efficiency
Technology is advancing rapidly, transforming many aspects of society, including how people communicate, navigate, treat diseases, and even defend their homes and countries. The internet of things (IoT) now has more electronics than ever to run better diagnostics, more sensors to increase autonomy, and better connectivity to avoid interference. IoT devices are becoming smaller for portability giving rise to battery-powered devices. These changes in the technology landscape are leading us toward a power revolution. A revolution that brings about longer battery life, super-fast battery charging with more sustainable and environmentally-friendly battery materials. Industries and research centers are leading the way to push the boundaries in battery development, manufacturing, and test.
The Next Power Challenge
The battery industry has come a long way from more than two decades ago. Today, battery manufacturers are constantly experimenting to find cheaper, lighter, and more powerful solutions to support the wide variety of battery-powered devices. Consumers demand longer-lasting and faster-charging batteries across industries, including consumer electronics, healthcare, automotive, and military. The healthcare industry relies heavily on better batteries to support medical equipment, such as blood pressure monitors, hearing aids, cardiac support equipment, and insulin pumps that are portable and convenient. Military applications may require power while in remote areas for extended periods between recharging or battery replacement.
Apart from battery manufacturers, IoT device manufacturers will consider battery characterization when designing new devices — right from design and prototyping to product development, product testing, and manufacturing. It is one of the most important considerations for IoT devices, giving them a distinct and marketable competitive advantage.
Device Design and Prototyping
Throughout the device design and prototyping process, a device designer keeps in mind the effects of the design and how it will affect the batteries.
Determine power strategy
The first step to prolong battery life is to determine the power strategy of the device. Before committing to a design, it is important to identify the functionality and usage of the new wireless device, recognize the hardware components and specifications, decide on the type of radio connection and thermal management, and consider software scalability, power up timing, and sequencing. Each of the items mentioned above affects the device design.
The next step is to select the correct battery for the device. The device designer needs to know the physical dimension and weight of the device, the battery chemistry that is suitable for the device, and how the battery will connect to the device. The device designer will include in the design the power requirement and determine whether it will meet the device’s nominal voltage, algorithm, and protocols for wireless transmission.
Lastly, characterize the chosen battery based on the power strategy and device design determined. Whether it’s the battery capacity, internal resistance, and open-circuit voltage, the device designer will want to verify it against the design.
The R&D engineer has an equally critical role in the effort to prolong the battery life of the IoT device.
One of the engineer’s tasks is to emulate the battery and test it against the device design, software, and firmware. This test covers various test scenarios with a combination of hardware and software designs without waiting for an actual battery to go through charge and discharge.
The next assessment confirms that the battery’s capacity and energy ratings align with the datasheet to verify that the runtime will meet the device’s design.
The R&D engineer will determine the battery’s age effect on the device performance and reliability under certain pre-defined test conditions.
The R&D engineer also performs a run-down test in various environmental conditions to realistically assess the battery performance in real-life situations.
Battery certification and compliance ensure user safety meets with the Underwriters Laboratories (UL) Certification and Waste Electrical and Electronic Equipment (WEEE) organizations’ guidelines.
Battery Test Comes With Challenges
Although the steps to design and develop wireless devices might sound straightforward, design engineers face many challenges. For example, a design engineer has to understand how a new device depletes its battery capacity.
With the miniaturization of IoT, the low-power IoT devices run on a very low µA current in the background to allow the device to function during idle time. The sleep current is also very low, compared to the current used when the device is active or transmitting. The design engineer has to isolate and test specific hardware sub-circuits since some sub-circuits must always run in the background to allow the device to function.
The design engineer will also test and characterize their device, its sub-circuits, and the
battery, both independently and in combination. The design engineer needs to validate and test the device to ensure it meets the proof of concept before going for mass production.
End-to-End Device Battery Test Solution
How can device designers accurately measure all transient activities to measure the overall current consumption of the IoT device effectively? How can the design engineers test the impact of their design and algorithm changes and validate them against complex customer use models?
The design engineer wants a solution that can help them perform battery characterization, emulation, cycling, current drain, and event-based power consumption analysis to optimize and maximize the device’s battery life.
The Keysight X8712A / N6705C DC power analyzer with its source measure unit and electronic load modules and three compatible software tools is an integrated solution that can help solve your battery life, battery drain, and battery emulation concerns. This integrated solution helps design engineers select, optimize, and validate battery performance by reducing battery testing time and complexities. Design engineers can then easily and accurately test and characterize their device and the battery to make informed trade-offs for optimizing battery run time.
Figure 1. An integrated solution for battery life, battery drain, and battery emulation
Battery technology and test tools are advancing rapidly to keep pace with the expectations and requirements. Design engineers should capture and analyze battery performance data early in the design and throughout the development process to avoid the costly and time-consuming rework required to fix problems late in the development cycle. Plus, the deep insight enabled by accurate battery life testing offers you the greatest chance of exploring new ways to extend and optimize your IoT device’s battery life.