DISCLAIMER: Starting a fire is illegal in most places. If a permit can be obtained in the area you are trying to start a fire, please do so before starting a camp fire. You are solely responsible for any damage you cause or any fines you may incur by starting a fire, and it is not my responsibility nor will I be held liable for your actions.
I have done this in a pinch, where I happened to have a device with a 9V battery, and I had some steel wool handy in a bag for cleaning off my knife. You will need a working 9V battery and some steel wool.
Step 1 – Prepare your tinder bundle
This tinder bundle needs to be held in your hand, place a bit of the steel wool about 1 inch by 1 inch and at least quarter inch thick, below the tinder bundle.
Step 2 – Build your twig teepee
Stack several dry twigs to form a teepee with an opening on one side to fit the burning tinder bundle. You can put small twigs and leaves inside to assist the flaming tinder bundle to start a larger flame.
Step 3 – Charge the steel wool
This step is VERY IMPORTANT. I place the battery on the edges of my hand near the pinky and float the tinder bundle above it. The battery terminals (plus and minus) should be facing up. Slowly lower the battery to the steel wool, and when it ignites, blow gently on the tinder bundle until a flame starts. The second the tinder bundle has a flame, open the edges of the hands to drop the battery. Open flame and batteries are a bad combination and can explode.
Step 4 – Place burning tinder into your twig teepee
Place the tinder bundle into your twig teepee. Gently blow into the teepee to start a larger fire. Add additional twigs and once the flame is large enough, add larger logs.