I have decided that it would be cool to have some of my small projects have built in lithium batteries instead of having to be hooked up to a 9 volt. I was wondering if anyone knew where to get small (about 600 to 1000 mah) Lithium Ion or Lithium Polymer batteries to power them that weren't too expensive ($5/amp hour). Thanks for advice.
Edit: I realized that $5/amp hour is probably not a thing unless I order thousands of batteries. I'm guessing that $10/amp hour is more realistic, but I still would like to know if anyone knows of any really good deals.

 

Hobby King (hobbyking.com) usually has good prices. You will need a special charger for LiPo's. Nominal voltage is 3.7V to 3.8V per cell.

Thus, a 3S battery will be 11.1V and a 2S battery will be 7.4V.

 

I was thinking I could maybe get some of these for the cells.
https://www.amazon.com/CreatePros-E...rd_wg=MckQF&psc=1&refRID=6W5G0M8X44WEBYXVP64E
I saw a video on youtube where someone took something like this apart and the batteries were actually rechargeable lithium polymer cells. I'll check out the hobby king website too.

 

I like the look of this one.
https://hobbyking.com/en_us/turnigy-2000mah-1s-1c-lipoly-w-2-pin-jst-ph-connector.html
I assume the little board on the battery itself is for over discharge protection, over current protection, and balancing. Not sure if it does over voltage protection.

 

A cheap battery usually has poor performance and duration.
Why do you guess about the little board on the Chinese battery if the seller does not say or know what it does? Maybe the little board was designed wrong and does nothing.

 

You make a good point. I shouldn't assume stuff about the board.

 

I hear that Lithium Polymer batteries don't have as many charge cycles in them as Nickel based batteries, so I didn't want to spend a lot of money on them.

 

I hear that Lithium Polymer batteries don't have as many charge cycles in them as Nickel based batteries, so I didn't want to spend a lot of money on them.

But your question was about lithium ion and LiPo, not nickle based batteries. Are you really asking about NiCd and NiMH?

 

My brand new Energizer Ni-MH batteries (Nickel-Metal Hydride) are guaranteed for up to 5 years or 400 charge-cycles. My high quality (not cheeep Chinese ones) Li-Po batteries are also guaranteed for 400 charge-cycles but their life is determined by how long they are wrongly stored with a full charge.

 

I guess I will look for a battery on ebay or amazon from a reputable seller then. Thanks for the advice.

 

I have decided that it would be cool to have some of my small projects have built in lithium batteries instead of having to be hooked up to a 9 volt. I was wondering if anyone knew where to get small (about 600 to 1000 mah) Lithium Ion or Lithium Polymer batteries to power them that weren't too expensive ($5/amp hour). Thanks for advice.
Edit: I realized that $5/amp hour is probably not a thing unless I order thousands of batteries. I'm guessing that $10/amp hour is more realistic, but I still would like to know if anyone knows of any really good deals.

Your best bet is to shop at RC Model Hobby supplier outlets. If you are in the U.S. you can find competitive pricing and low shipping costs at the following to name a few: ( Lok for "1S LiPo when tou search).
http://www.valuehobby.com/power-systems/batteries/1s-lipo.html
https://www.amainhobbies.com/search?s=1s+lipo

If you need just a few , you could also scavenge Li-Ions from used (or abandoned) Laptops, Mobile phones etc., but follow all safety precautions when disassembling , charging and usage.

 

I may try to salvage batteries from disposable chargers since they can contain lithium ion batteries and the ones in the chargers are smaller than the 18650s found in many laptops.

 

disposable chargers

What are "disposable chargers"?

 

This type of thing. I saw a video of something very similar to this being opened up and the battery was a rechargeable lithium ion. Also appears to have a VU meter that I may be able to salvage for op amps, LEDs, and a button. Makes me cringe that people throw these things away because its horrible for the environment and the batteries are perfectly good.
https://www.amazon.com/gp/product/B...b82-5121-915b-13f684dd6327&pf_rd_i=7073960011
Edit: fixed link

 

I may try to salvage batteries from disposable chargers since they can contain lithium ion batteries and the ones in the chargers are smaller than the 18650s found in many laptops.

I think you mean the cell phone chargers (also called "Power Banks" by some ). I did take one apart and it had a flat pack 1300 mAH - actually two 650mAH's in parallel. I tested it with the Multipurpose charger I have that I use for charging my RC plane batteries, and I was pleasantly surprised that it showed a capacity of 1300 mAH when charged and discharged at 1A.

 

I have never seen a one-time-use disposable charger. The ad might be wrong and there are some cheap Chinese carbon-zinc "Super Heavy Duty" cells in it.

Amazon, Ali and ebay sell cheap Chinese junk, I doubt there are reputable sellers there.
I buy Name Brand Li-Po batteries from my local hobby store and they all work perfectly. My friend bought some cheap Chinese Hobby King Li-Po batteries and many did not work.

 

I might buy a cheap disposable power bank just to see if the battery is in fact a lithium ion and if it is, how good it is. Sadly, I don't know of any hobby stores in my area because the local radio shack closed down and I don't get out much.
Edit: Took a look on google maps and there is 1 or 2 hobby stores near me that may have lithium batteries, but I will still probably buy any batteries online due to the convenience. There are reputable hobby stores online, right? It also appears that google maps think that a barber shop is a hobby store for some reason.

 

My local hobby stores have many products stocked and made by Horizon Hobby who sell online and ship to 100 countries.
I laugh at Google maps. They show stores in the middle of wide streets because DUH! they don't know that even numbers are on one side and odd numbers are on the other side. A kennel for caring for my dog for two days was shown on the wrong side of a huge highway. GPS navigation makes similar errors.

 

I will check Horizon's website out.

 

Just wanted to throw out an idea that people may be able to use. There are tons of batteries on ebay for old phone models that have removable batteries such as the galaxy s3. These 2200 mah 3.7 volt batteries are around 5 bucks, which seems like a pretty darn good deal. Combine that with a 3d printed casing to hold it and a TP4056 and you have an inexpensive way for powering small projects. What do you guys think?