Batteries for IoT – How to Choose the Best One

What factors should you consider when selecting batteries for IoT? The rapidly growing trend of connected devices, expected to reach 29 billion by 2030, has increased the pressure on product developers and suppliers working with various IoT components.

Choosing the right battery is crucial for ensuring reliable performance, long lifespan, and compatibility with the device's requirements. Factors such as voltage, capacity, size, and battery chemistry must be carefully evaluated to meet the specific needs of each IoT application.

Variety in Battery Chemistries

Depending on the specific IoT application, its design, and usage, various battery chemistries are available on the market:

• ·  Lithium-ion batteries are most commonly used in devices where high energy density and long cycle life are essential.

• ·  Nickel-Metal Hydride (NiMH) or Nickel-Cadmium (NiCd) batteries are preferred for IoT devices that rely on next-generation networks, such as 5G or LPWA (Low Power Wide Area), or for devices that need to operate across a wide temperature range.

Another key consideration is the device’s power requirement and runtime on a single charge. Some IoT devices demand significantly more power than others, and frequent recharging may be undesirable. In such cases, a battery with higher power output should be chosen.

Does Size Really Matter?

Many IoT devices share a common characteristic: their small size. This often requires the use of compact and lightweight batteries. For such products, it is essential to choose a battery that does not occupy too much space or add excessive weight.

The most common choice for these applications is rechargeable lithium button cells or other coin-type batteries. However, some IoT devices require replaceable batteries, which can include lithium-ion or nickel-metal hydride options, depending on the device’s design and power requirements.

Factors Impacting Battery Performance

If an IoT device is used in extreme temperatures or harsh environments, it is crucial to choose a battery designed to withstand these conditions. The battery must also operate seamlessly with other components and its surroundings to minimize interference, which could potentially damage the device.

Even slight temperature changes can significantly affect a battery’s capacity and lifespan. To ensure proper operation, select a battery suited to the device’s specific temperature conditions. For example, the typical acceptable temperature range for lithium-ion cells is -20°C to 60°C. Exposure to high or very low temperatures can damage lithium-ion batteries in several ways:

• ·  Accelerated aging, leading to faster degradation.

• ·  Loss of power, caused by increased internal resistance.

• ·  Thermal runaway, which can have catastrophic consequences for both the device and its surroundings.

What Affects the Price of IoT Batteries?

Price is often a key factor when selecting a battery, regardless of the project type. As a decision-maker, you need to balance cost with performance. Here are the main factors to keep in mind:

• ·  Customized Solutions: The more complex the application design, the higher the cost of developing a custom battery solution capable of storing sufficient power for system operation.

• ·  Bulk Orders: Ordering in large volumes can reduce the per-unit cost. For batteries with long shelf life and consistent demand, bulk purchasing can result in significant savings.

• ·  Battery Type: Different battery chemistries affect overall costs. Lithium-ion and solid-state batteries, for example, require sophisticated manufacturing processes, which increase their price. However, their longer lifecycle and higher capacity often justify the cost through reduced operational and replacement expenses.

• ·  Supplier Quality and Compliance: Battery quality varies significantly across suppliers. Not all provide the necessary certifications and regulatory documentation required for importing batteries into markets such as Europe. Always verify compliance with standards like UL, CE, or RoHS. A lower price may result in higher long-term costs.

• ·  Battery Management System (BMS): For lithium-ion batteries, the BMS is crucial. It balances cells, monitors temperature, and prevents overcharging or over-discharging. While a more advanced BMS increases cost, it ensures safety and prolongs battery life. Some BMS designs may also require additional components or design considerations to integrate properly with the battery system.

SUNJ – Guiding You in Your Battery Choice

Now that you’ve seen how many factors can influence battery selection for your IoT devices, you may still have questions about your specific project. SUNJ has assisted numerous customers across Europe in finding batteries perfectly suited to their requirements.

Feel free to reach out to us with your questions by filling out our contact form or sending an email to SUNJ. The consultation is completely free and requires minimal information from your side. Let us handle your concerns and guide you toward the best battery solution for your IoT project!