When buying double- or triple-A batteries, you commonly have a choice between two types, namely lithium-based and alkaline-based.
What exactly is the difference between the two? And which type should you buy for your particular use case?
When selecting AA or AAA batteries, consumers commonly face the decision of choosing between alkaline and lithium varieties. - Image Credit: Nomad_Soul via Shutterstock / HDR tune by Universal-Sci
Durability
The most notable difference between lithium and alkaline batteries is durability. This does not only concern how long they last on a single charge but also how long they can be stored and how many times they can be recharged (if rechargable to begin with, of course).
SHELF LIFE
Typically, lithium batteries have a shelf life that is longer than that of standard alkaline batteries. Lithium batteries last for up to 12 years and, in rare cases, even 20 years in storage, whereas alkaline batteries usually last for about 5 to 10 years. On top of that, lithium batteries have a lower rate of self-discharge when stored.
RECHARGE CYCLES
The number of times that a lithium-ion battery can be recharged is a lot higher than that of an alkaline battery. Lithium batteries can survive between 4,000 to 10,000 cycles, significantly surpassing the (approximate) 300 cycles that alkaline batteries tend to last.
BATTERY LIFE
Lithium batteries also often outperform alkaline batteries in terms of battery life on a single charge. They can last up to three times longer than alkaline batteries, primarily due to their higher capacity and consistent voltage maintenance throughout their lifespan.
Interesting related article: Why does smartphone battery life get worse as it gets older? (Universal-Sci)
Chemical Composition and Energy Output
When it comes to the internal workings, alkaline and lithium batteries differ significantly. Alkaline batteries generate power through a reaction involving zinc powder, manganese dioxide, and graphite. This alkaline-based electrochemical process delivers a steady 1.5V per cell.
Lithium batteries, conversely, release energy through a reaction between manganese dioxide and lithium. This unique chemical reaction contributes to a higher energy density in lithium batteries, offering a wider voltage range, typically from 1.5V to 3.0V per cell.
Alkaline batteries use an alkaline electrolyte, which allows for a simpler charge and discharge process, while lithium batteries use a non-aqueous electrolyte, providing a higher voltage, energy density, and a lower self-discharge rate.
Wider operating temperatures
Lithium batteries are known for their broader operating temperature range compared to alkaline batteries. Typically, lithium-ion batteries can function effectively in temperatures ranging from -20°C to 60°C, with their optimal performance observed between 0°C and 45°C.
In contrast, alkaline batteries are generally advised for use within a narrower temperature window, from 0°C to 50°C. This wider temperature tolerance of lithium batteries makes them a more versatile choice for diverse environmental conditions and a broader array of applications.
Environmental impact
The environmental effects of alkaline and lithium batteries vary in multiple dimensions, stemming from their production, usage, and disposal processes.
The production of lithium batteries is associated with a higher carbon footprint, largely due to the energy-intensive methods required for lithium extraction and the subsequent long-distance transportation involved. Additionally, the complexities of recycling lithium batteries often result in them being relegated to landfills, posing risks of soil and water contamination.
Image Credit: bews via Shutterstock / HDR tune by Universal-Sci
In contrast, alkaline batteries, which utilize more commonly available materials, typically have a smaller carbon footprint. Their recycling process is comparatively simpler, and many countries have well-established recycling programs for alkaline batteries.
Nevertheless, if not disposed of correctly, alkaline batteries can still be a source of environmental pollution. This is particularly true in cases of incineration, where heavy metals like mercury, cadmium, zinc, and lead can be released into the environment.
Choosing Between Alkaline and Lithium Batteries: When to Use Each Type
Deciding between lithium and alkaline batteries requires weighing factors such as performance, lifespan, and environmental impact.
Lithium batteries are ideal for devices that demand high energy output and consistency, such as digital cameras and high-performance toys.
In contrast, alkaline batteries are better suited for low-drain devices that require a steady but modest power supply, making them a common choice for everyday household electronics, especially because they are often less expensive.
Sources and further reading:
Lithium batteries with polymer electrodes (Applications of Electroactive Polymers)
Alkaline Storage Batteries (Journal of The Electrochemical Society)
Why battery-powered vehicles stack up better than hydrogen (Universal-Sci)
AAA battery test - (Hardware.info)
Why does smartphone battery life get worse and worse as it gets older? (Universal-Sci)
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