Charging a battery without a charger: 10 steps (with pictures)

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Charging a battery without a charger: 10 steps (with pictures)
Charging a battery without a charger: 10 steps (with pictures)

Have you ever had an empty battery, for example in your camera, just when you need the device the most? Or worse, a dead phone in an emergency. You can't always have a charger with you. For those who like to improvise (or need to), the following information will come in handy.


Method 1 of 2: Use a battery to charge a battery

Charge a Battery Without a Charger Step 1

Step 1. Remove the battery from the device

You must have access to the battery terminals. Keep in mind that the battery of some mobile phones is not accessible, so be aware of the dos and don'ts with the phone model you have. On most (but not all) Android and Windows phones, the back cover can be removed if you apply the right pressure in the right place. This does not apply to most Apple products.

Charge a Battery Without a Charger Step 2

Step 2. Find some AA, AAA, or 9 volt batteries

Unlike the power that comes from a wall outlet (alternating current), the power in common household batteries is no different than the batteries in your phone or camera.

  • It may be surprising that it is suggested to charge one battery with another battery. Perhaps you were expecting a magic trick that would allow you to charge the battery without an alternative power source, but such is not possible. One of the fundamental laws of physics (the law of conservation of energy/conservation of mass) makes it clear that you don't get anything for nothing. Learn to live with it.
  • It is recommended that you simply charge your battery instead of trying to route power to your battery from another source. Using incorrect amperage and voltage can damage complex circuitry, it's not worth the risk.
Charge a Battery Without a Charger Step 3

Step 3. Identify the positive and negative terminals of each battery

On AA and other household batteries, the terminals will be marked. For most cell phone batteries, the positive terminal is closest to the edge, while the negative terminal is usually farthest from the edge (there may be three or four terminals, but the center terminals are used for temperature control and other functions).

Charge a Battery Without a Charger Step 4

Step 4. Make sure the voltage of the battery to be charged matches the other batteries (AA, AAA or others with sufficient power)

Normally, the batteries of today's phones require a voltage of more than 3.7 DC to charge. So several AA or AAA batteries or a 9 Volt battery will be needed to charge. Remember that normal household AA and AAA batteries provide 1.5V each. So to get more than 3.7 V you need three AA or AAA batteries connected in series: 1.5 V + 1.5 V + 1.5 V = 4.5 V. This will be your power supply if you use AA or AAA batteries.

Charge a Battery Without a Charger Step 5

Step 5. Take two pieces of metal wire

Ideally, these will be insulated in plastic, except for the ends.

Step 6. Tape or clamp the wires to the battery that will supply the charge and the battery that will receive the charge

The wires can get hot (but if you do it right, they probably won't). It will also take a while for the charge to be transferred. So make sure you don't have to hold them all the time.

If you're using AA or AAA batteries, it's a good idea to daisy-chain them together before connecting them to the receiving battery. You do this by connecting the negative terminals of all small batteries to the negative terminal of the receiving battery, and the same for the positive terminals

Step 7. After a while your battery should be charged

Mind you, it probably won't be fully charged, but you'll still be able to use the device you need for a while.

Method 2 of 2: Using the rub trick

Step 1. Remove the battery from the electronic device

Hold it in your hands.

Step 2. Rub the battery hard

Use both hands to create enough friction and heat. Do this for 30 seconds to several minutes.

  • Note: Your battery will not be charged. Some commentators on the internet suggest that rubbing your battery with extra charge, possibly due to the build-up of static electricity. This interpretation is incorrect.
  • Lithium-ion batteries, like all normal batteries, release electricity as a result of chemical reactions. These reactions, as predicted by the Arrhenius equation, become stronger as the temperature increases. In essence, you improve the conductivity of the battery by increasing its temperature.

Step 3. Put the battery back into the electrical appliance

You may only have had power for a few moments, so use them well.


  • Make sure to turn off the device before removing the battery, otherwise the settings of the device may be changed.
  • Try to charge only rechargeable ones. Never attempt to charge alkaline batteries or other batteries intended for limited use.
  • Do not overcharge the battery. Lithium batteries can be explosive when overcharged.

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