Introduction: DIY Carbon Heated Sleeping Bag
Do you want to stay warm even in a light sleeping bag? With the carbon cord heating element on you can increase your sleeping bag rating by 10 degrees.
The carbon cord is very soft and does not interfere with sleeping. Unlike nichrome wire it can withstand multiple bending. You can expand and collapse your sleeping bag again and again and carbon will never break.
I improved my sleeping bag in just one hour, see how easy it is.
Step 1: Shopping List
1. A sleeping bag you would like to improve.
2. 30 feet of 3mm carbon fiber rope and now on Amazon
3. 12V dimmer.
4. 15 feet of wire. I like ultra flexible silicone wire 18 AWG.
5. Duct tape.
6. Female DC Power Socket Jack Plug Connector
7. USB power bank 12 Volt and 2 Ampere at least recommended.
Step 2: Just Wrap It!
For our project we used 6 pieces of 5 feet of carbon rope 3mm. A large length (30 feet total) of heating elements provided uniform heating.
But the most important thing is that a large number of segments provided a small electric current on each of the elements (about 0.4 Ampere). With such a small current it is very easy to ensure a reliable contact between carbon cord and electric wire. Simply strip a small section of wire and wrap it around the carbon cord.
1. Open the sleeping bag and evenly distribute the carbon rope on the inner surface, as on the photo.
2. Prepare several lengths of wire and lay them as shown in the photo and on an equivalent circuit.
3. Strip wires at the intersection points with the carbon ropes and wrap it tightly.
4. Connect female power socket plug connector.
Step 3: And Just Duct Tape It!
Secure carbon ropes and wires with duct tape.
With such a length and voltage of 12 volts, the carbon rope will only heat up to 30-40 degrees Celsius. At this temperature the duct tape will not melt or peel off.
I've already used this electric heated sleeping bag in several hikes and the duct tape is still securely in place. It is soft enough and does not interfere with sleeping. The volume of the collapsed sleeping bag did not change. I think this is a good solution for express DIY designs but in the next project I want to use a sleeping bag with a detachable lining to sew the carbon cord to the lining.
Step 4: Just Power It and Stay Warm
I had a very inexpensive summer sleeping bag with a comfortable temperature of +15 degrees Celsius. After installing the heating it became comfortable even at a temperature of +5 degrees Celsius. The carbon cord emits nearly 30 watts of heat. This level is typical of commercially available products. For example Ravean sleeping bag has about 40 Watts.
Using a dimmer, I can smoothly adjust the temperature and the run time. Carbon heated sleeping bag can be powered by the most of 12v USB power banks, but you can also connect it to any of 12-24 volt power supply. For example, to the power adapter of your laptop, to the car battery. The carbon cord heats up in a few seconds, I climb into the sleeping bag, press the button and immediately feel the warmth both above and below.

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13 Comments
Question 2 years ago on Step 2
I have a question about its durability like the on-going usage until now.
And is there any problem such as the overheat from short-circuit, electric registance, etc when using this sleeping bag?
Your candid opinion, please.
Answer 2 years ago
We had no problem at all. We never washed sleeping bag but I had to wash the same carbon heated vest a few times and it still works fine
Reply 2 years ago
I see, and appreciate your helpful kindness!
6 years ago
Normally carbon fiber particles that come from cutting are very bad to inhale and could lead to cancer, and touching them will severely irritate skin. Is it safe to cut this carbon cord without breathing protection? is it safe to handle without gloves? If you attach to the inside of the sleeping bag and sew fabric over it instead of duct tape, will carbon fiber particles make it through the fabric and irritate your skin when you sleep?
Reply 6 years ago
There are two types of carbon fibers: one is designed for reinforce (pan based, pitch based). Process temperature is about 1500C and 10-25 hours for carbonization. Consist of thick fibers, tough in touch and cannot heat evenly. Very strong. Bad to inhale. If it has a resin (prepreg carbon) it may cause cancer because or resin.
https://www.pccomposites.com/wp-content/uploads/20...
It can heat also but you would not feel comfortable if you wear it.
Our
carbon fiber tape is viscose based. It's biocompartible material and used for wound healing and human body implants.
https://www.google.ru/url?sa=t&rct=j&q=&esrc=s&sou...
It feels like a fine silk. That kind of carbon required
much more temperature (2500-2800C) and manufactoring time (70-100
hours). Not so many factories made it. It is safe.
6 years ago
Maybe I missed it but what kind of autonomy do you have with this battery? Great project
Reply 6 years ago
Commercially available Ravean sleeping bag has about 40 Watts and battery pack 15600 mAh. You can switch it to 40w (run time 4,5h), 20w (9h) or 14w (13,2h).
My sleeping bag has about 30 Watts and has a dimmer. For now I use very small 3400 mAh power bank:
http://www.ebay.com/itm/272487602764?_trksid=p2057...
The run time at full power just 1 hour but I usually use it for a few minutes only to get warm before sleep. Of course I can use a bigger battery pack or reduce power with my dimmer to extend the run time.
6 years ago
Looks warm. What is the battery you use in picture? and what connection do you make to battery? It looks like female connection of end of dimmer ...
Reply 6 years ago
We used this DIY power bank with 18650 inside:
http://www.ebay.com/itm/272487602764?_trksid=p2057...
and this power bank:
http://www.ebay.com/itm/XTPower-MP-10000-External-...
And yes, I had to change connector to male.
6 years ago
Is there a benefit to using the carbon fiber rope over the carbon fiber flex tape?
Reply 6 years ago
It's easy to connect wire to rope just wrap it. And one more thing, with the same power you feel it more hot because of less heating area. Just feeling but feels good.
Reply 6 years ago
Thanks!
6 years ago
This is absolutely genius. I need to do this, it'll be nice when the night gets really chilly when camping.