The power supply is the first building block of your electronics project. You always have to choose power supply carefully before starting your product. Choosing your power supply depends on few factors
- What is the amount of current your circuit going to draw?
- In which condition or environment, your product is going to use?
- Do you need to charge the battery or replace the battery when dead?
- Size of the product
- Cost of the product
Let’s see few different types of available DC power supply and there use cases.
AA Size Battery:
AA Size or Double-A size battery are the widely available battery in the market, this comes in both non-chargeable or chargeable form. Generally made of NICd or Lithium Ion. These batteries are 1.5V, so if you want more voltage from this, you can use more batteries in series connection.
You must have seen coin cell batteries on your wearable device(like you watch) or inside your PC/Laptop motherboard. The size of this battery varies from 5mm to 25 mm in dia. These batteries are suitable for lower power circuit, which consumes current in micro or Nano Amp.
These are widely used batteries in electronics product, which are rechargeable. You can find these batteries inside toys, gadgets, handheld device, mobile phone, laptop or cameras. These batteries need special care for charging. LIPO chargers are made to protect the battery from over charge or over discharge.
This is a very old and common form factor use in toys, radio and a personal device like a torch. You can get this easily from the market and can use in your projects. You need a connector to connect it to the circuit as show in above image. These are made of alkaline.
Apart from battery, there is always an option of dedicated power for your own electronics lab experiments.
You can buy small wall charger or you can use your mobile phone / laptop travel charger, for you experiments in your lab. Be sure about ratings before connecting it the circuits.
Typical wall charger looks like this. Generally, it comes in 5V, 9V, 12V with a current rating of 500mA to 2A. These are handy and cheap. You can get this under 2$ in the market.
Lab Bench Power supply:
If you love to experiments in your electronics lab and works on critical projects, you should get your own bench power supply from market starting at $25 like shown in above image. These are generally variable power supply and you can get a volt meter and Ammeter attached to it.
We hope this gives you some idea of choosing battery for your electronics need. You can always read more about each of from Wikipedia.