Alkaline batteries are obsolete — but not for the reason you'd think

Summary

The video argues that alkaline batteries are not necessarily the best choice for today’s low-power devices—not because they perform poorly, but because many devices use so little energy that alkaline batteries’ main advantage matters less. The host compares budget and name-brand options, then revisits carbon-zinc batteries, once the standard single-use battery.

Battery Tests and Findings

Using configurable electronic load testers, the host compares how much energy different AA batteries deliver under different loads. A key distinction is:

• Energy density: The total energy a battery can provide.
• Power density: How quickly it can deliver that energy.

Alkaline batteries can lose usable capacity under high-power demands: their voltage sags, so a device may stop working even though the cells are not fully drained.

• At a 1-watt load, a four-AA set of Great Value batteries ran for nearly 6.5 hours; Rayovac High Energy lasted 6 hours 45 minutes; Energizer Max lasted 8 hours 25 minutes; and Duracell lasted 9 hours 34 minutes.
• At 2.5 watts, capacity dropped substantially. For example, the Great Value set delivered about half the energy it had under a gentler test, while even the Duracells lost 43%.
• With slow, gentle discharges, alkaline brands performed much more similarly. Duracell reached about 3 watt-hours per AA cell, while tested store-brand cells approached that figure.

The host concludes that differences in total energy between alkaline brands are often small in low-drain use, even though Duracell performed best in the tests. Its advantage is most relevant in devices that draw a lot of power and drain batteries quickly.

The host argues that such uses are now less common: power-hungry electronics generally use integrated rechargeable lithium batteries, while many remaining AA- and AAA-powered devices—such as remotes and clocks—draw little power.

Carbon-Zinc Batteries

The host also tests “super heavy duty” carbon-zinc AA batteries, including cheap Dollar Tree cells and Panasonic cells.

• Dollar Tree carbon-zinc batteries delivered roughly 0.62–0.84 watt-hours per cell, depending on the package.
• Panasonic carbon-zinc batteries delivered about 1.2 watt-hours per cell under a gentle test. The host estimates that a well-performing cell could reach around 1.25 watt-hours.
• This is substantially less than alkaline batteries, but the gap matters less in low-drain devices than it would in older, power-hungry portable electronics.
• Carbon-zinc cells perform especially poorly under heavier loads. At a 1-watt load, the Panasonic cells lost more than 70% of their gently measured capacity. In the example, Duracell alkalines lasted about seven times longer.

The host’s conclusion is that carbon-zinc batteries could be reasonable for low-drain devices if good-quality cells were available at a sufficiently low price. However, cheap store-brand alkaline batteries already offer much more energy for a modest cost, so carbon-zinc batteries may not have a strong price advantage beyond the very cheapest options.

Leakage and Practical Considerations

The host favors carbon-zinc batteries partly because of their leak-mitigation designs. Some tested cells have a protective wrap or disc intended to limit damage from corrosion and escaping electrolyte. Carbon-zinc batteries can still corrode and leak, and the host notes that the impression they behave better in real-world use is anecdotal rather than statistically proven.

Alkaline batteries can leak caustic potassium hydroxide and damage battery contacts or electronics. The host suggests that improved leak protection for alkaline batteries might be worthwhile, even if it reduced capacity somewhat.

The host also notes that old carbon-zinc batteries found in remote controls were still working, including some past their printed expiration dates. This is not presented as formal shelf-life evidence.

Overall Takeaway

For high-drain devices, alkaline batteries—especially Duracell in these tests—can be much better than carbon-zinc cells. For common low-drain applications today, the capacity difference may matter less, and inexpensive alkaline batteries are often adequate. The broader point is that disposable batteries may be becoming less relevant as rechargeable options improve.

The host previews a future examination of nickel-metal hydride rechargeable batteries, including whether their historical trade-offs still limit their usefulness. The video also criticizes quoting battery capacity only in milliamp-hours, arguing that watt-hours communicate usable energy more clearly.

Reviews, Guides, and Tutorials

• Comparative battery testing: Great Value, Rayovac, Energizer, Duracell, Dollar Tree, and Panasonic AA batteries.
• Technical explanation: Energy density versus power density, voltage sag, and why batteries can appear “empty” before their stored energy is fully used.
• Practical guidance: High-drain devices favor alkaline cells; low-drain devices may work well with cheaper alkaline or suitable carbon-zinc cells.

Main Speaker and Source

• Technology Connections narrator/host: Presents the tests, measurements, product comparisons, and analysis.