1. Lithium-Ion Batteries
Lithium-Ion is a type of battery in which the cathode (negative electrode) is made of a Lithium-based compound. During use, lithium ions migrate from the positive electrode to the negative electrode through a separator membrane that is dipped in a liquid electrolytic solution. The anode (positive electrode) is usually made up of graphite or other carbon-based materials that provide intercalation sites for the lithium ions.
Arduino Nano can be best powered using a Lithium-Ion Battery. These batteries are not highly-priced and are available in a convenient 18650 form, enclosed in a tough metal case.
2. Lithium Polymer
Lithium Polymer is a type of Lithium-ion battery that has a polymer as its electrolyte instead of a liquid electrolyte. Lithium Polymer or LiPo batteries have a greater energy density (more energy per unit weight) than other Lithium-ion batteries. This makes them apt for applications where space and weight are limited.
Lithium Polymer batteries are high-performance batteries that are required for devices that consume a lot of power, like drones. Hence, they are slightly costlier and are not ideal for powering an Arduino Nano.
3. Rechargeable/Non-Rechargeable AA batteries
AA batteries are the most commonly seen single-cell batteries in electronic appliances. They can be of both primary (non-rechargeable) and secondary (rechargeable) types. Primary batteries are usually of two types – alkaline and zinc chloride. Secondary batteries can be Lithium-ion, Nickel-metal Hydride (NiMH), or Nickel-Cadmium (NiCd).
4. Other batteries
Other types of batteries can also be used to power an Arduino Nano. However, the processes involved may be quite complex depending on the type of battery used.
How To Power Arduino Nano With Battery
- Lithium-Ion Batteries: You can easily power an Arduino using a Li-ion battery. Li-ion batteries are available as single-cell 18650 or 14500 (AA-size) batteries.
- Battery Holder: The choice of battery holder will totally depend on the size of your battery. Please use a high-quality holder as low-quality holders can often lead to loose contact and cause unwanted behavior.
- Battery protection board: Li-ion batteries cannot be charged directly. This is because a fraction of an overcharge or overvoltage can lead to hazardous situations like a fire or an explosion. Hence, they are charged using a battery protection board that cuts off power the moment a battery reaches its maximum allowed voltage (usually 4.2V).
Follow These Steps:
Step 1- Place the battery into the battery holder.
Since 18650 cells are larger than 14500 (AA) cells, they will require a bigger holder. Holders must be tailored to the size of the battery to make proper contact. The contacts have some kind of spring mechanism to ensure a tight hold. The terminals of the holder may or may not have wires soldered to them for connection.
Step 2- Connect Terminals of the Battery Holder with the Protection Board
If your battery holder already has two wires connected, then simply connect them to the protection board. Otherwise, you need to carefully solder two wires (one for positive and one for negative) to the respective terminals of the holder.
You can start by charging the Li-ion battery. Connect the positive and negative terminals from the holder to the corresponding terminals on the protection board. Make sure the polarity is correct otherwise the battery may be damaged.
Step 3- Now Charge the Battery with a Micro-USB Phone Charger
Any standard USB-based phone charger can be used to hook up the protection board. Once charging is complete, the protection board will indicate it using a green LED light. Normal Li-ion batteries will show a voltage of around 4.2V when fully charged.
Step 4- Connect USB port of Arduino Nano
Disconnect the protection board from your phone’s charger and connect it to the micro-USB port on the Arduino Nano. The Arduino Nano should now light up to indicate that it is running.
Power consumption of Arduino Nano
The Arduino Nano’s current draw will be depending on the following:
- Devices that have been interfaced with it like displays, external sensors, etc.
- The supply voltage also determines the Nano’s current draw. For a 9V power supply, the current draw is usually around 4.83mA. This can go down to 3.41mA if the supply voltage is reduced to 3.3V.
- The power consumption will also depend on whether the Arduino Nano is fully awake or is sleeping. So, in turn, it will also depend on the software that you are running on it.
- The current consumption will also vary depending on the Arduino’s make and the voltage regulator that has been used on the board.
- Finally, the clock speed of the onboard Atmega328 controller will also determine the current consumption. Generally speaking, 8MHz clock speeds are preferred for low-powered applications. However, if the Arduino has a 16MHz crystal oscillator on board then it will need to be replaced with an 8MHz one first.
It is very important to understand the tolerable voltage levels of an Arduino or any electronic device before powering it. The best way to determine this is by studying the specification sheet from the manufacturer. Going above tolerable levels can cause irreversible damage to the board.
Another important thing to keep in mind in Li-ion-powered projects is to monitor the charge on the battery. This can be achieved by measuring the voltage across the terminals with a multimeter. This voltage level should never be greater than the maximum or less than the minimum voltage as specified by the manufacturer.