A D cell battery, also known as a D battery, is a kind of an electrochemical cell. This means that, much like the other AA or AAA batteries you normally use in your flashlights, transmitters, and radio receivers, it comes in the form of a cylindrical chamber consisting of an electrolyte paste and an electrode rod which passes through it.

It will also have electrical contacts positioned at each end. The positive end will have a bump or nub, while the negative end will have a small depression. So now you might be wondering, what then is the difference? What exactly makes the D cell stand out and what are some of the best D cell batteries out there.

D Cell Vs. C And AA Cells: How Much Voltage Do They Have?

If you take a look at your typical AA batteries and C batteries, they are all listed as having 1.5 volts. Well, this is the same with D cells. They have the very same nominal output voltage of 1.5 volts. However, despite this, there is still a difference between the three. 

The first and most obvious difference is that D cell batteries are bigger in size. The standard D cell will normally have a length of about 2.38+-0.04 inches (60.5+-1.0 mm) and a diameter of 1.31+-0.04 inches (33.1 +-1.0 mm). This means they won’t just fit into any regular appliance, which raises another question. If they have the same voltage ratings, why not use the smaller AAA batteries on everything and make things smaller and lighter? Well, that is where the second major difference comes in – the battery’s current.

You see, in an electrical device or circuit, there will be two main things. One is voltage, and the other one is current, both of which can be tested using some of the best multimeters. To explain the two more easily, we shall compare them to a water pipe, with water flowing through it. In this case, the voltage will be like the water pressure that pushes the water down the pipe. Current, on the other hand, will be the amount of water that flows down the pipe. 

So Where Do D Cells Come In?

So, now that you know the difference between voltage and current, you will find that for some electronics to operate efficiently, they will need more current, but they won’t need more voltage. If your appliance needs a lot of current and you try setting it up with tiny batteries, it will not work as well. This is where the D cell batteries come in. They work by supplying more current to the appliance than your average C cell battery could. 

You see, D cells have a larger capacity, which lets them hold a greater mass of the anode material. (This is usually an electrode that consumed inside the battery to supply electrical current). Because D cell batteries store more energy, they are able to supply current for longer than the other cells, even at equal current levels. However, in some cases, rechargeable type AA batteries can run longer when compared to disposable D cells.

D cells also come in rechargeable form. However, sometimes the rechargeable ones will have a significantly lower capacity than the single-use, primary or non-rechargeable type. This is because they are internally actually a C or AA cell. Most of them, however, are true D cells that hold greater capacities that the C or AA batteries. In fact, while AA and C batteries will have a typical capacity of 24,00 and 7,800 mAh respectively, D cell batteries will have as much as 12, 000 mAh.

Need More Voltage?

As for when you need more voltage, you can simply add a couple of batteries together. In most electronics, this would mean that you arrange them such that the positive end of one battery touches the negative end of the other one. This is referred to as adding them in series. Therefore if you add two batteries in the series, each having 1.5 volts, in the end, you will have a total of 3 volts.

However, there is another less common arrangement called parallel. Here, the batteries would be arranged in a straight line, and the negative will join the negative, and the positive will join the positive of the next battery. In this case, if you connect two equal batteries, the voltage will remain the same as that of one battery. So if you are connecting, say 3 D cell batteries, the voltage will still remain 1.5 volts. 

It is important to note that you have to be careful only to connect batteries of equal voltage in this type of arrangement. For example, if you connect a 3-volt battery with a 1.5-volt battery in parallel, there will be an argument about which voltage it should be at. You should avoid this at all costs.

Beware of Non-Standard D Cells!

Another thing is you have to be keen on the kind of battery you buy. Some will be labeled as being D sized or take the shape of a D cell battery, but they will be a bit different. Some of them are actually rechargeable D’s, which consist of sealed lead-acid cells and will have a nominal voltage of 2 volts. The capacity of these kinds of cells will usually be a little lower (about 5000 mAh).

The invention of cell signal technology is a game changer in the way people work, communicate, and exchange information. This generation has become so reliant with instant communication that everywhere, there’s always someone who needs to check if there phone has a four-bar signal strength.

However, cell signals can be unreliable at times, even in urban areas.

Two common reasons for not having a good cell signal are: (1) the phone or device is out of range of a cell tower, and (2) there are signal interferences, like the weather.

These two problems can easily be fixed by:

Relocating to a Better Coverage Area

If a phone signal is not detectable in one place, the easiest remedy is to move to another area where there is better signal.

This shouldn’t be a problem in dense urban areas as most major phone carriers have multiple cell towers in one city.

For those living in the countryside, they can check with their phone provider for a map of their cell tower coverage. Or better yet, one can use their own cell phone to locate the signal by turning on their phone’s dB display.

Users can do that through these steps:


  1. Activate Phone Mode
  2. Dial *3001#12345#*
  3. Enter Field Test Mode
  4. Check the notifications bar to see the dB reading

*Note: This method won’t work on an iOS 11 phone and models that use Intel modems.


  1. Access Settings
  2. Go to General
  3. Select About Phone
  4. Then click Network or Status to show the dB value

After the dB meter is on, one can just trace the signal and find the best spot with the strongest reception.

Adding a Phone Signal Booster

Of course, if moving out is out the question, another way to strengthen the cell signal is by installing a signal booster, which can also double as a secondary cell tower inside a home.

A signal booster is used to extend the area of a cell network. It works by amplifying what signal it receives from the original cell tower then covers its own area of transmission.

For devices that rely on 3G or 4G networks, there are boosters, like the WeBoost Connect 4G, that are specifically made to increase phone signal and wireless Internet.

Signal boosters, signal repeaters, and signal extenders all work the same way. Getting a booster may mean spending some money for it, but it’s the best option for those who regularly have connectivity problems due to weak cell signals.

Remove Obstructions

Electronic appliances and other metallic objects, not to mention concrete walls, can disrupt cell signals. The signal is strongest if it’s out in the open and away from television, computer, or any electronic devices.

What others fail to know is that the reflective part of a mirror is a metallic sheet, so it also blocks cell signal if a device sits directly in front of it.

Devices that use signals also heavily affect its strength. Examples of these are microwave ovens and wireless telephones.

Do Not Block the Phone’s Antenna

All phones have an antenna to pick up cell signals. It’s obvious with old phones, but new models have theirs tucked inside the phone.

Usually, phone antennas stand upright with the device. Holding the phone in a horizontal, landscape grip may block the antenna and dampen its reception.

So one should keep their phones up if they want to get a good signal.

Stay Connected

According to Pew Research Center, 95 percent of America use a phone. Whether people use it for personal or professional reasons, there’s no denying that mobile technology has become a necessity to almost everyone.

Knowing these simple ways of improving cell signal will come in handy in keeping one constantly connected to the world.