Personal technology might often come with built-in rechargeable power sources, but the humble alkaline battery is still the go-to for a whole host of electronics in your home. Whether it's your TV's remote or that handy fan that keeps you cool in the summer, alkaline batteries are here to stay. It might surprise you to hear that not all batteries are created equally. Some have a longer shelf life, while others run for longer before they need to be replaced. So, which should you trust with powering your devices and accessories?
- Best Alkaline Batteries for Your Devices in 2025
- Best AAA alkaline battery
- Best AA alkaline battery
- Best C alkaline battery
- Best D alkaline battery
- Best 9V battery
- Best alkaline batteries compared
- How we test batteries
- Other alkaline batteries we've tested
- Alkaline batteries FAQ
Here at CNET, we've put a wide range of alkaline batteries through our testing to find the longest-lasting options. From standard AAs to 9-volts, we conducted discharge tests and calculated the cost per battery to help you get the best bang for your buck.
All of these batteries are top performers for your everyday devices and are also a great option for people who need reliable power for kids' toys and more. We’re looking at you, Reddit folks, asking about the best batteries to buy.
Our guide will walk you through all our top picks based on real-world performance, starting with Amazon's own brand of AAA batteries.
Pros
- - Reliable discharge
- - Great value
The competition for the best AAA battery was closely contested, as all competing brands demonstrated similar performance in our discharge test. Affordability and reliability played a significant role in our evaluation.
Amazon AAA batteries emerged as the most reliable during our discharge test. They exhibited consistently repeatable results across three different runs and boasted the longest average discharge time, at 28 minutes and 32 seconds.
Moreover, if you're considering buying in bulk, this option is by far the better choice. At the time of this publication, the 36-pack was priced at less than $14, translating to approximately 40 cents per unit. Now that's true value.
Pros
- - Reliable and long-lasting power
- - Good value
AA batteries are likely the most popular battery size, given their widespread use in a variety of electronic devices. They don't hold as much charge as a C or D battery, which means you're probably going to be replacing them a lot. Again, it comes down to bulk price and performance.
The two leading AA battery brands, Energizer and Duracell, stood out in the competition. While they displayed similar performance, Energizer had a slight edge. A single Energizer AA Max battery powered three fan motors arranged in parallel for an impressive average of 30 minutes, 15 seconds, marking the best score among the group. The decisive factor between the two brands turned out to be price.
Furthermore, Energizer AA Max batteries are the second most affordable option. The 20-pack is currently priced at approximately $14 at the time of this publication. With outstanding performance and an affordable price, if you're in the market for AA batteries to power your electronics this summer, this is the optimal choice.
Pros
- - Outperformed the competition
This one was straightforward. Duracell outperformed its competition convincingly. The only caveat is that this may not be your most budget-friendly option. Since C batteries are primarily used for medium-drain devices like cameras, radios and even some intruder alarms, longevity and reliability are paramount.
In our discharge test, Duracell C-type batteries powered four fan motors in parallel for an outstanding average of 25 minutes and 42 seconds, nearly doubling the average duration achieved by other competing brands. Quality sometimes comes at a price, and Duracell C batteries are no exception. The 10-pack is priced at roughly $20 at the time of this publication, totaling roughly $2 per unit, the highest price per unit in this category.
Pros
- - Excellent performance
- - Long lasting
Cons
- - Second most expensive
D batteries are predominantly used in high-current drain devices that require prolonged running times and emergency gadgets such as flashlights, radio transmitters, and even some water heaters. It should come as no surprise that, in this case, we particularly value performance over price.
Amazon D batteries excel in performance. They were able to sustain our five-motor parallel circuit for nearly 18 minutes on average, the highest score in this category. Impressively enough, they maintained a voltage output higher than 1.2 volts throughout each of the three runs. That's a lot of juice.
That said, they are the second priciest option on our list. The 4-pack is priced at approximately $9 at the time of this publication, translating to roughly $2.25 per unit.
Pros
- - Outperformed the competition
- - Most cost-effective option
9-volt batteries deliver higher voltage but possess less overall charge, resulting in a shorter lifespan compared to their 1.5-volt counterparts. They are ideal for high-voltage, low-drain applications such as smoke alarms, portable electronics, tools and even the multimeter we used in this test.
In our focused analysis, we observed the battery's ability to maintain high voltage output throughout its usable life. Amazon 9-volt batteries not only significantly outperformed other brands in terms of discharge time and voltage output under load, but they also stood out as the most cost-effective option, priced at only $1.16 per unit for a 24-pack at the time of this publication. This makes it the only brand we tested in this category available for less than $2 per unit. In our discharge test, Amazon 9-volt batteries sustained our battery test rig for over 36 minutes -- nearly three times longer than their competitors. This makes them the clear winner across all metrics.
Best alkaline batteries compared
Amazon Basics | Energizer | Duracell | Amazon Basics | Amazon Basics |
Alkaline High Performance | Max | Coppertop C | D Cell Alkaline | 9V Alkaline |
AAA | AA | C | D | 9V |
8, 12, 36, 100 | 2, 4, 8, 10, 12, 20, 24 | 2, 4, 8, 10, 14 | 4, 12, 24 | 4, 8, 12, 24 |
$0.85 (8-pack) | $2.02 (2-pack) | $2.24 (4-pack) | $2.25 (4-pack) | $2.45 (4-pack) |
1340mAh | NA (~3,000 mAh typical) | NA (~7,000 mAh typical) | NA (~10,000mAh typical) | NA (~550mAh typical) |
For this round of testing, we gathered four of the most popular battery brands and tested five battery categories, including AAA, AA, C, D and 9-volt. Our objective was to find out which battery manufacturer offered the best value for your money. To assess battery performance, we used our custom-built battery test rig and timed the longevity of each battery, paying attention to their voltage output over time, and compared the difference in price per unit.
Battery performance and voltage drop
Measuring battery voltage output is more complex than simply sticking multimeter probes on the positive and negative ends of the battery. For instance, AA, AAA, C and D batteries are rated at 1.5 volts. If you measure voltage output directly on the battery, the reading may be close to 1.6 volts, which is generally a good sign for a new battery. Even batteries that are no longer usable can display a value equal to or higher than 1.5 volts when measured directly. The correct approach is to test voltage output under a load condition, such as when the battery is connected to a resistor or powering a device. Meet the CNET Labs Battery Test Rig:
CNET's custom-built battery test rig accommodates five battery types, including AAA, AA, C, D and 9-volt. The breadboards and connections allow for parallel and series circuit arrangements, depending on battery voltage.
Gianmarco Chumbe/CNETComponents include two breadboards, one for 1.5-volt batteries and one for 9-volt, six motor fans that can be arranged conveniently either in series or in parallel, a switch for each circuit, one multimeter for voltage readouts, a chronometer and five battery slots for each type of battery: AAA, AA, C, D and 9-volt.
The testing logic is simple but revealing. To get the full picture, let's refresh ourselves with a bit of electronic basics. The number of active load components and the circuit arrangement depend on the type of battery under test. For the 1.5-volt group (AAA, AA, C and D batteries), we arranged the circuit loads in parallel, increasing the number of loads according to the capacity of the battery. This ensures that, regardless of the power source and number of loads, all load components are exposed to the same amount of voltage from such a power source — in this case, any of the 1.5-volt batteries. For example, AA batteries are tested using three motors in parallel, ensuring that all three motors get 1.5 volts each.
We use parallel arrangement on our test rig. From left to right, the 1.5-volt battery source (either AAA, AA, C or D), a voltmeter and motor array. The setup allows two motors to be active at all times, allowing the addition of up to five motors.
Gianmarco Chumbe/CNETFor the 9-volt types, we arranged six load components in series. A series arrangement evenly distributes the voltage from the power source across all load components. Since each of our fan motors takes at least 1.5 volts to run, using a 9-volt battery provides 9-volt/6 loads = 1.5-volt per load.
Six motors are arranged in series. The 9-volt battery provides equal voltage distribution (1.5-volt) across each of the loads.
Gianmarco Chumbe/CNETHaving established the basics, we proceed to testing. First, we ensure to connect our multimeter probes in parallel and take an initial voltage reading. Then, we make sure our circuit arrangement is adequate for the type of battery under test and flip the switch on. We start our timer and monitor the test, recording data readouts for voltage output under load every minute until the very last fan stops spinning. We run a "last man standing" competition. In our test logic, the battery that sustains the load arrangement the longest wins. The voltage drop allows us to see how efficiently the battery maintains a high voltage output given the test conditions. In this regard, the slower the drop in voltage, the better.
Here are the results, starting with an overall look at the average discharge time for each battery we tested. Longer bars indicate batteries that lasted longer in our test rig.
Here's a more detailed look at those results, with the specific, minute-by-minute dip in the average voltage readings for each battery during each test. Again, we're looking for the batteries that last the longest in this test, but more specifically, we're looking for batteries with as gradual a voltage drain as possible.
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Price per unit
The cost of batteries can vary greatly depending on where and when you buy them. For that reason, we sought out the most economical source for each battery and compared the price per unit. Check out the table below, which we'll update regularly:
Duracell AAA: Second-highest price per unit but a close contender for best performance. Not a bad deal.
Energizer AAA: Lowest performance among the options, and the second most affordable. Not the best quality choice.
Amazon Basics AA: Impressively low performance, nearly half the average run times of competitors. However, it's the cheapest option.
Duracell AA: Highest price per unit, but the second-best performer and a close contender for the best pick.
Rayovac AA: Second most costly AA battery with moderate performance. Not necessarily the top option available.
Amazon Basics C: Lowest price per unit among C types, significantly cheaper than the competition. A good choice for bulk purchases.
Energizer C: Priced closely with others but lacking in performance, securing last place with an average run time of only 4 minutes.
Rayovac C: Priced similarly to competitors, offering low performance but not the worst.
Energizer D: A potential splurge pick with great performance but higher cost compared to others.
Duracell D: Falls in the median for both performance and price, lacking any remarkable features.
Rayovac D: The most affordable D battery, suitable for bulk purchase with acceptable performance.
Energizer 9V: Hard to justify due to its higher price and failure to outperform the competition.
Duracell 9V: The most expensive option, tying for last place with Rayovac in terms of battery lifetime.
Rayovac 9V: Takes the last place in performance but offers better pricing than the competition.
Rayovac AAA (out of stock): Most expensive AAA battery with room for improvement in performance, ranking second to last.
What is an alkaline battery?
Alkaline batteries are disposable batteries that use MnO2 (manganese dioxide) and Zn (zinc) as electrodes to generate electrical power. They are known for their reliability and are commonly used in a wide range of electronic devices.
Can different sizes of alkaline batteries be used interchangeably?
It's not recommended. Each size provides a specific voltage and capacity tailored to certain devices. Incorrect sizing may lead to improper functioning or damage to your electronic devices. I wouldn't risk it.
How should alkaline batteries be stored?
Store them in a cool, dry place at room temperature, avoiding extreme temperatures and especially humidity. Proper storage helps maintain their performance over time. Always take batteries out of toys and electronics you don't plan on using for a long time.
What is the shelf life of alkaline batteries?
Alkaline batteries typically have a shelf life of several years, but it's important to check the expiration date on the packaging. Expired batteries may experience reduced performance. Properly storing them helps with longevity.
Two of the most popular battery brands are Duracell and Energizer. But is there a difference between the two? There is, actually. For the most part, both brands are reliable, but they offer different advantages. Energizer is better for affordability and decent performance for low-drain devices, while Duracell is typically better for longevity and reliability in high-drain devices.