The future of batteries and energy storage in consumer electronics

Batteries, including the popular lithium-ion and lithium-polymer types, are at the heart of modern electronics—from smartphones and laptops to electric vehicles and advanced energy storage systems. Amid increasing energy demands and efforts to reduce carbon emissions, the development of energy storage technologies has become a significant element of modern innovation. In this article, we present current trends in battery technology, along with their advantages, limitations, and examples of existing applications. We also answer questions such as how cells work and how different types of batteries differ.

How do battery cells work?

A cell is the fundamental component of a battery or rechargeable battery, generating electricity through chemical reactions occurring between its components. It represents the smallest unit capable of generating electrical voltage and serves as a crucial component in energy storage systems. It works by converting chemical energy into electrical energy in the form of direct current. The fundamental operating principle of a cell lies in the potential difference between two electrodes immersed in an electrolyte. Electrons move from the anode to the cathode through an external circuit, allowing current to flow. Simultaneously, ions in the electrolyte migrate between the electrodes, maintaining chemical equilibrium. To achieve higher voltages or capacities, cells are assembled in series or parallel arrangements. Such configurations enable batteries to be adapted to the requirements of various devices, enhancing their efficiency and overall performance. When assembling battery-powered electronics, it is important to ensure that the cells are stably connected to optimize their performance and durability.

The main components of the cell

• The anode (negative electrode) is the site where the oxidation reaction (electron donation) occurs. It is typically made of a metal or a reducing material, facilitating efficient chemical reactions.
• The cathode (positive electrode) is the site of the reduction reaction (electron acceptance). It is most commonly made of oxidizing materials, such as metal oxides, enabling efficient energy storage.
• An electrolyte is a conductive medium that facilitates the transport of ions between the anode and cathode. It can exist in various forms, such as liquids, gels, or solids, depending on the type of cell and its application.
• A separator is a thin layer positioned between the anode and cathode, preventing direct contact and thereby avoiding short circuits. Simultaneously, the separator permits ion flow, which is essential for sustaining the chemical reaction within the cell.

Types of battery cells, ranging from alkaline to lithium-polymer

Primary cells, such as alkaline or zinc-air batteries, are commonly used in everyday devices like remote controls, watches, and flashlights. By contrast, secondary cells, including lithium-ion batteries, are utilized in advanced energy storage systems, such as electric vehicles and renewable energy solutions.

• Primary cells are single-use energy sources that cannot be recharged after depletion. Common examples include AA and AAA batteries, which utilize zinc-carbon, alkaline, or zinc-air chemistry.
• Secondary cells, commonly referred to as rechargeable batteries, are reusable energy storage devices that can undergo repeated charging cycles through reversible chemical reactions. The most common types include lithium-ion, lithium-polymer, nickel-cadmium, nickel-metal hydride, and lead-acid batteries.

What formats do battery cells come in?

Cylindrical cells are characterized by their distinctive shape and are widely utilized in portable electronics, power tools, and electric vehicles. Examples of common sizes include 18650 and 21700 (these numbers indicate the cell’s dimensions: the first two digits represent the diameter in millimeters, while the next three specify the length in tenths of a millimeter). For instance, an 18650 cell has a diameter of 18 mm and a length of 65.0 mm. One of their key advantages is durability. Their robust metal casing offers excellent resistance to mechanical damage, while standardized sizes streamline manufacturing and integration across diverse applications. Additionally, the cylindrical shape promotes efficient heat dissipation. However, their disadvantages include lower space efficiency compared to other cell types, potentially resulting in larger battery sizes that may not be ideal for space-constrained devices.

Prismatic cells, characterized by their rectangular shape, are commonly utilized in laptops, electric vehicles, and energy storage systems. Their optimized design enables a higher energy density compared to cylindrical cells. The rectangular shape facilitates more efficient packing in space-constrained devices. Simultaneously, the flat design enhances efficient heat dissipation. However, disadvantages include higher production costs and increased susceptibility to mechanical damage compared to cylindrical cells.Pouch cells are recognized for their flexible and lightweight design, making them commonly used in smartphones, tablets, and drones. Their advantages include a high energy density, enabled by their lightweight packaging. Their design allows for the adaptation of shape and size to meet the specific requirements of the device. However, their disadvantages include reduced mechanical stability and increased vulnerability to physical damage, such as punctures or swelling.

Modern energy storage technologies – lithium-ion batteries and alternatives

Lithium-ion batteries, extensively used in smartphones, laptops, and electric vehicles, are a type of rechargeable battery that employs lithium ions as charge carriers. They are characterized by a porous carbon anode and a metal oxide cathode. Each cell typically generates a nominal voltage of approximately 3.6 volts. This technology enables up to double the energy storage capacity compared to NiMH batteries of the same weight and size. Their advantages:

• High energy density compared to older technologies such as lead-acid or nickel-cadmium batteries, lithium-ion cells can store a significant amount of energy relative to their weight and volume. This enables portable devices to operate longer and electric vehicles to achieve greater range on a single charge. 
• Cyclic stability and durability under standard conditions, Li-ion batteries can go through 300 to 1,000 full charge and discharge cycles before their capacity drops to about 80% of their initial value. Their lifespan varies depending on factors such as depth of discharge, operating temperature, and protective mechanisms used.
• Low in self-discharge, Li-ion batteries lose about 1-2% of their capacity per month, which is much better compared to older generation technologies such as NiMH, which lose between 10% and 30%. This makes Li-ion batteries particularly useful in devices that are used less frequently.
• The versatility of Li-ion technology makes it applicable to a wide range of devices, from consumer electronics to industrial systems and renewable energy storage systems.

Disadvantages:

• Dependence on raw materials such as lithium and cobalt.
• The risk of overheating in lithium-ion batteries requires the implementation of appropriate protective systems to ensure their safe use, particularly in devices with high energy demands.

Are you wondering whether a Li-Ion battery is safe when making your purchase?

It’s worth knowing that Li-Ion batteries can use a variety of protective technologies to enhance safety and minimize the risk of overheating. The extent of protection depends on the design, purpose and manufacturer. Simple cells in everyday devices are equipped with basic protection mechanisms, while more advanced systems, such as those in electric vehicles or medical equipment, use comprehensive solutions. Popular protections include PTC thermistors that limit current flow if the temperature rises, circuit interruption systems (CID) that operate in critical situations, and safety valves that release excess gases. Some models use thermosensitive separators that stop the transport of lithium ions at high temperatures, preventing further heating. In addition, advanced battery management systems (BMS) monitor parameters such as voltage, current and temperature to ensure optimal operating conditions. As a result, protective technologies can be precisely tailored to different requirements and applications.

Lithium-polymer (LiPo) batteries are advanced batteries that use an electrolyte in the form of a gel or thin polymer, sandwiched between layers of electrodes, which distinguishes them from traditional lithium-ion (Li-ion) batteries. This design eliminates the need for metal enclosures. This technology allows for a design with greater flexibility, making LiPo batteries a preferred choice for devices requiring customized design solutions. Note that the assambly of lithium-polymer batteries requires special precision, since their flexible design is more susceptible to mechanical damage. Advantages:

• Average capacity ranges from 1000 to 5000 mAh (at 3.7 V per cell). More advanced designs can achieve capacities of up to 20,000 mAh.
• Lightweight and flexible, LiPo batteries are significantly lighter than traditional cells. Their design allows for customization in size and shape to meet the specific needs of individual devices. These batteries are commonly used in devices such as portable defibrillators and medical sensors.
• High energy density means more capacity with less volume. This makes them ideal for applications requiring maximum energy efficiency.
• Minimal self-discharge, making them efficient even after long periods of non-use.
• A safe design without metal enclosures minimizes the risk of explosion in case of mechanical damage to the cell.

Disadvantages of LiPo batteries:

• Shorter lifespan, LiPo batteries are less durable than traditional Li-ion cells, meaning fewer charge and discharge cycles before losing performance.
• Vulnerability to damage, the soft and flexible casing makes LiPo batteries more susceptible to punctures and mechanical damage.
• Storage and charging requirements. To ensure a long lifespan and avoid safety problems, it is necessary to follow specific charging and storage procedures (e.g., avoiding overcharging or discharging below minimum voltage).
• Production cost, manufacturing LiPo batteries is more expensive than traditional lithium-ion batteries.

Alkaline batteries are one of the most popular types of primary cells, widely used in everyday electronic devices. They operate based on a chemical reaction between zinc (anode) and manganese dioxide (cathode) in an alkaline environment, typically using potassium hydroxide as the electrolyte. Characteristics of alkaline batteries:

• The average capacity ranges from 600 to 3000 mAh (depending on the size, such as AAA, AA, C, D).
• During operation, they provide a voltage of about 1.5 volts and remain stable during use. This feature is especially crucial for devices that require a reliable power supply, such as remote controls, watches, or medical equipment.
• They offer higher capacity compared to traditional zinc-carbon batteries, allowing devices to run longer.
• Their low self-discharge rate allows them to be stored for several years without significant capacity loss.
• They are non-toxic, reducing the risk of environmental hazards, and readily available at almost any store, making them one of the most common consumer choices.

Disadvantages of alkaline batteries:

• Disposable, alkaline batteries are not rechargeable, which means they can generate more waste.
• They run out faster in devices with high energy requirements, such as cameras and electric toys.

Zinc-air batteries are a specific type of primary cells that use oxygen from the air as the cathode and zinc as the anode. They are known for their very high energy density and low production cost. These batteries are widely used in hearing aids, medical devices (such as cochlear implants), as well as in some military and industrial technologies. Features:

• The average capacity ranges from 620 to 2000 mAh (for hearing aids).
• Typical voltage is 1.35-1.4 volts.
• Their very high capacity makes them ideal for devices that require long-lasting operation.
• They are manufactured from non-toxic and easily recyclable materials.
• Limited lifespan after opening. Once exposed to air, they rapidly lose capacity, even when not in use.

Nickel-metal-hydride (NiMH) batteries are popular secondary cells (rechargeable batteries) that offer higher capacity and no memory effect compared to their predecessors – nickel-cadmium batteries. NiMH batteries are widely used in electronic equipment such as digital cameras, electric toys, remote controls, as well as in portable tools like drills and other rechargeable devices. They were also popular in hybrid vehicles such as the Toyota Prius. Features:

• The average capacity ranges from 600 to 2500 mAh (for standard AAA and AA sizes). For professional applications, capacities can reach up to 10,000 mAh for larger industrial-grade cells.
• Typical voltage is 1.2 V (which is lower than that of alkaline batteries but offers greater stability).
• Average energy density is lower than that of lithium batteries but higher than nickel-cadmium batteries.
• They have no memory effect and can be recharged at any time without adversely affecting their capacity.

Batteries in numbers

• Global demand for lithium-ion batteries is projected to grow almost sevenfold between 2022 and 2030, reaching 4.7 TWh by 2030. This growth is primarily driven by the development of electric vehicles and the increasing demand for renewable energy storage. The automotive sector, particularly electric passenger cars, is expected to account for more than 60% of this growth (Statista), (Statista).
• In 2021, the lithium-ion battery market was valued at approximately $54.6 billion, representing a significant increase compared to previous years, with forecasts predicting growth to around $257 billion by 2030 (Statista).
• Global demand for lithium, a critical raw material in battery production, is projected to exceed 1.4 million tons of lithium carbonate equivalent by 2025, marking a 53% increase compared to 2023 (Statista).

Future energy storage technologies

1. Solid-state batteries (SSBs), or solid electrolyte batteries, promise higher safety, longer lifespan, and greater energy density than lithium-ion batteries. They are currently under development and testing.

• Advantages: Greater performance, lower risk of catching fire, application in electric vehicles.
• Disadvantages: High production costs, complex manufacturing process.
• Applications: Electric vehicles, consumer electronics, renewable energy storage.

2. Lithium-sulfur (Li-S) batteries, this technology has the potential to offer higher energy density than traditional Li-ion batteries by using sulfur as the cathode.

• Advantages: Low material costs, high energy density.
• Disadvantages: Short cycle lifespan, electrode degradation.
• Applications: Drones, electric vehicles, military applications.

3. Hydrogen-based energy storage. Hydrogen technologies offer a new way to store energy by converting it to hydrogen and vice versa. This is particularly promising for renewable energy storage.

• Advantages: No carbon emissions, vast energy potential.
• Disadvantages: High infrastructure cost, low efficiency rate.
• Applications: Renewable energy storage, hydrogen-powered vehicles.

4. Ultracapacitors, this technology enables rapid charging and discharging of energy, making it well-suited for high-power applications.

• Advantages: Long lifespan, high energy efficiency.
• Disadvantages: Low energy density compared to batteries.
• Applications: Electric vehicles, portable devices, renewable energy sources

Investments and patents in SSB technology

SSB technologies are gaining significant attention around the world, especially in countries investing in advanced energy storage technologies. Japan, a leader in the field, accounts for over 50% of global patents in SSB technology, with companies such as Toyota holding 582 patents in this area. The United States and Germany are also experiencing significant growth in the number of patents and investments in solid-state technology development. These data highlight the intensity of global competition in this field, as well as the importance of innovation toward more sustainable battery technologies (Statista)(Statista). However, the introduction of solid electrolyte batteries involves a change in the approach to component assembly, which will affect future manufacturing processes.

Environmental impact and sustainability

Environmental impact and sustainability are among the key challenges of today’s economy, where the growing demand for energy necessitates innovative technological solutions. The development of modern batteries, such as solid-state batteries (SSBs) and lithium-sulfur (Li-S) batteries, contributes to enhancing the efficiency of renewable energy storage and minimizing CO₂ emissions, which is a significant step toward achieving sustainability goals. In this context, enhancing recycling processes and efficiency, reducing dependence on scarce raw materials, and investing in alternative technologies such as hydrogen storage are crucial in minimizing carbon footprints and building a greener future. In the context of green solutions, electronics assembly should also take into account the possibility of recycling and reusing raw materials.

An innovative approach to energy storage technology

Batteries and energy storage are the foundation of modern electronics and technology. While current technologies offer high performance, their limitations highlight the need for further research and investment in future solutions. New technologies, such as solid-state batteries and hydrogen storage, have the potential to greatly enhance energy management on a global scale. If you’re interested in learning more about cutting-edge technologies or are looking for support in designing devices using innovative solutions, the Device Prototype team is ready to assist with your project – get in touch with us today!