Most chargers should also work with any brand of rechargeable battery that’s the right type and size. While AA and AAA are the most common sizes supported, some chargers fit other sizes like C or D; check each product for the complete list of compatible sizes. Others can charge up to 16 or even 40 batteries at once. For most people interested in a basic and reliable charger, the Energizer Recharge Pro will get the job done for household devices. It comes with two AA starter batteries and is straightforward to use. To get more advanced features and controls, you might want to consider the Nitecore SC4 Superb Charger, which has a display and lets you customize the charging current. If you use enough gadgets to warrant a supply of rechargeable batteries, here are the best rechargeable battery chargers to keep them topped off. The Recharge Pro also provides quick, basic updates on your batteries’ charge status through a set of indicator lights on its front. Red means charging has started; yellow means halfway done; and green means full. You’ll also hear beeps when charging stops and starts or if the charger senses a problem with the battery. One inconvenience is you have to charge batteries either two or four at a time; it can’t charge one or three. Fortunately, this isn’t too hard to get around, especially with the starter set of four Energizer rechargeable AAs that come included. The Recharge Pro offers substantial value for any home looking to keep a decent number of battery-powered devices going. Supported Battery Sizes: AA, AAA | Number of Charge Slots: 2 or 4 | Charging Current: 500mA (AA), 220mA (AAA) | Input: 100-240V AC outlet | Status Indicators: Colored LEDs, sounds Adding to the convenience is the ability to charge those batteries in any number and combination, along with LEDs that change color to indicate each battery’s charge status. Eneloop also happens to be a trusted manufacturer of some of the best rechargeable batteries you’ll find, so the four included AA batteries offer excellent value. One potential downside is that charged batteries may come out somewhat warm to the touch. This is due to the extra current that provides the faster charging speed. If charge time isn’t a factor for you, a slow charger is less expensive and slightly better for the longevity of your battery cells. Supported Battery Sizes: AA, AAA | Number of Charge Slots: 1 to 4 | Charging Current: 750mA (AA), 275mA (AAA) | Input: 100-240V AC outlet | Status Indicators: Colored LEDs A red LED light turns on for each side that’s charging, shuts off when charging is complete, and blinks to warn of bad batteries. An auto cut-off function helps make sure your batteries don’t overcharge. When you plug the unit into a wall outlet, a green light will indicate the USB port is ready to use. You can then plug in a USB cable to charge a smartphone or other device. This port is a convenient extra feature that lets the charger double as a USB wall plug, but note it will not charge your rechargeable batteries while it’s charging something else through the USB port. You also can’t unplug it from the wall and use your batteries as a portable power bank to charge other devices on the go. Supported Battery Sizes: AA, AAA | Number of Charge Slots: 2 or 4 | Charging Current: 600mA (AA), 350mA (AAA) | Input: 100-240V AC outlet | Status Indicators: Colored LEDs It automatically detects the type and capacity of each battery you put in and selects the optimal charging current. You can also fine-tune the settings manually, such as choosing a current as high as 3A (amperes) for faster charging. You can then monitor detailed information like the battery status and charge time on the high-definition LCD screen. In addition to supporting standard rechargeable batteries at AA, AAA, AAAA, C, and D sizes, the Nitecore SC4 also works with a variety of lithium-ion batteries. You can charge batteries individually or, depending on the size, up to four at a time. As a bonus, the SC4 offers USB output, so you can charge devices like a phone or laptop after your batteries are done charging. You can also buy it in a bundle that includes a battery case and a car adapter so you can charge on the road. Supported Battery Sizes: AA, AAA, AAAA, C, D, 18650, many more | Number of Charge Slots: 1 to 4 | Charging Current: Max 3A (x2), 1.5A (x4) | Input: 100-240V AC, 12V DC | Status Indicators: LCD screen The charger is like a magnetic-locking case you can fold up, with convenient handles that make it easy to tote around. Each half has 20 battery slots and receives power from its own input port; the included power cable plugs into one wall outlet and splits up to power the two sides. This arrangement allows you to plug in just one side if you’re not using both. Also, note that you’ll need to charge in even pairs of batteries rather than odd numbers. Helping you keep track of all your charging batteries are lights for each pairing that change from red to blue when fully charged. There are even four total USB output ports if you want to charge other devices simultaneously. Supported Battery Sizes: AA, AAA | Number of Charge Slots: 2 to 40 (in pairs) | Charging Current: max 200mA (x20) | Input: 100-240V AC | Status Indicators: Colored LEDs The design also includes practical advantages, like vents built into each bay to keep temperatures lower while charging is in process. Overheating shouldn’t be a big problem anyway, as the charge current is on the low side compared to other home chargers. You’ll typically be leaving it running overnight to charge multiple standard AAs to full capacity. The latest version of the product lists a new feature meant to detect and automatically repair damaged cells, but actual performance will vary. Supported Battery Sizes: AA, AAA | Number of Charge Slots: 1 to 16 | Charging Current: 200mA (AA), 150mA (AAA) | Input: 100-240V AC outlet | Status Indicators: Colored LEDs The charger comes with a Micro USB cable that you can plug into a power source, with the added option of a more modern USB-C input if you want to use a USB-C cable instead of Micro USB. Unfortunately, the unit doesn’t come with the USB power adapter that goes into your wall outlet, and it specifically requires a 5V 2A adapter. This type of adapter is usually a larger plug compared to the smaller 1A adapters that won’t provide enough power for the charger to work properly. Even with the right power supply, charging tends to be slower than with standard AC-powered chargers, especially if you’re trying to charge multiple large batteries. Supported Battery Sizes: AA, AAA , C, D | Number of Charge Slots: 1 to 8 | Charging Current: 900mA (AA/AAA), 1800mA (C/D) | Input: 5V 2A DC (Micro USB or USB-C) | Status Indicators: LCD screens

Number of Batteries

It’s usually easy to see how many slots a battery charger has. Many can hold four batteries, though others can fit eight, 16, or more. Chargers that support larger battery sizes may have them taking up two of those slots. You’ll also find that inexpensive chargers often require you to charge batteries in pairs and that charging more batteries at once often means longer charge times.

Charge Time 

The age, condition, and capacity of your rechargeable batteries affect how fast they can charge. In terms of the charger, supplying stronger electrical currents means quicker charging times. Chargers on the fast side can typically fill a set of four AAs in about three or four hours. Some people may prefer a slower charge, however, as it tends to be slightly better for preserving a rechargeable battery’s lifespan in the long run.

About Our Trusted Experts

Anton Galang started working as a tech writer and editor in 2007 and has covered a variety of products, gadgets, and games for Lifewire. He uses an Energizer Recharge Pro to maintain the battery supply for the many toys in his home (both his kids’ and his own).