High Drain Small Batteries!

[Solomon Laser]

Hello All,

I plan to do some keychain and pocket laser builds and I am having trouble finding a battery that fits my needs.

I am interested in 1/2AA and 2/3AA (10280) batteries. Jayrob has a keychain build that uses a 10280, but the highest current I can find for a battery of that type is 300ma, which is a lithium ion. They have 450mah ones that are thionyl chloride, but they only output 30ma of continuous current. Some one claimed an output of over 600mw for one of Jayrobs keychain lasers, but of course they never gave the link to the battery.

I bought several 1/2AA thionyl chloride batteries at 1200mah but they perform worse than a AAA 350mah lithium ion.

I will make some phone calls to the manufactures today, but my goal is one of the batteries I listed above with the most output!!

 

[steve001]

Hello All,

I plan to do some keychain and pocket laser builds and I am having trouble finding a battery that fits my needs.

I am interested in 1/2AA and 2/3AA (10280) batteries. Jayrob has a keychain build that uses a 10280, but the highest current I can find for a battery of that type is 300ma, which is a lithium ion. They have 450mah ones that are thionyl chloride, but they only output 30ma of continuous current. Some one claimed an output of over 600mw for one of Jayrobs keychain lasers, but of course they never gave the link to the battery.

I bought several 1/2AA thionyl chloride batteries at 1200mah but they perform worse than a AAA 350mah lithium ion.

I will make some phone calls to the manufactures today, but my goal is one of the batteries I listed above with the most output!!

Check out illumn.com. They carry a lot of brands.

 

[Benm]

One thing to consider is that the batteries with the highest capacities are not always the ones that can supply the most current over a short period of time.

The construction of a lithium battery is a tradeoff between maximum capacity and minimum internal resistance. In most cases this goes mostly to maximum capacity as things like laptops, phones, etc do not typically empty their batteries in an hour or less.

Batteries intended for things like drones can have the trade off the other way, since they are often drained in minutes and need to deliver a lot of power in the brief time they last. You might consider looking there for a solution, though the form factor will probably not be 1/2 AAA size or anything user-friendly like that... the contact resistance of battery holders like that would be a problem.

 

[DTR]

Yep the capacity "mAh" does not tell you the max sustainable discharge rate and usually the higher the discharge capabilities of the cell the lower the capacity. I find those that go looking for the highest capacity end up getting lower quality batteries with fake specs. Anyway check these out. 80mAh with a 10C+ discharge rate.
https://www.matchboxinstruments.com/collections/chargers/products/mbi-nuke-10250-li-ion-battery

 

[Solomon Laser]

All of the links you provided are very helpful!

I talked to a large battery company yesterday and they confirmed the lithium thionyl chloride batteries just have too low of a discharge, even the spiral wound ones. The LTC batteries would be good for low powered lasers that last forever.

I am very close to choosing a battery, and then I will make custom hosts that can accommodate a large variety of didoes and powers. They should be affordable so anyone on here can build the quality medium powered laser they want!

 

[Benm]

I hope you can find something that suits your needs.

The high current ones (say 10C and up) are good for things that operate very shortly and require a lot of power (like drones), but i don't see many applications where this is useful for a laser. Surely it could be bright for its size, but then again only last a few minutes.

Could be good for something like an insanely high powered pointer, but don't really thing buiding those is the best of ideads - something that looks so innocent but is yet so dangerous to use... perhaps you could feature at least some locking mechanism in there!

 

[Solomon Laser]

Anyone know of CR2 high drain batteries? It looks like most have a continuous current of about 1100mah.. I was hoping for around 2-2.5A.

The max continuous current does not matter because it is not sustained, correct?

 

[Benm]

First and foremost, CR2 is a form factor.

There are non-rechargeable CR2 cells that have a pretty good capacity (1 Ah or so) on the marked sold by major brands like duracell and energizer. These are intended for photo cameras and such, and could perhaps push out 2 amps, though they were not built for high power output - they are built for long shelf life, these are the things you leave in their packaging for 10 years and still work just fine after.

The rechargeabl kind, which i presume you are looking for, is a different story. There are tons of CR2-sized lithium cells on the market, but finding any good ones has proven very difficult. Capacities are claimed at random values, 600 mAh, 1000 mAh, whatever they come up with. Considering the size and chemistry it is dubious the 600 mAh could be real.

The big problem is there is no way to tell: there are TONS of ebay listings for ultrafire and similar CR2 rechargeable cells with various claims to their capactiy. If they were actually 500 mAh you should be able to pull 2.5 amps from them easily (it's only 5C, any decent lithium cell will do that at least briefly).

Sadly the real capacity is often much lower, perhaps 200 or 300 mAh, and that means 2.5 amps would mean 10C or more, which may be too much to ask of an already ilconstructed cell.

If anyone knows a reputable and reliable vendor of CR2 cell's i'd be interested as well. Not even for high current performance, but just something that actually has the capacity claimed on the label.

I've seen some that make a more realistic claim of 220 mAh capacity, but in that case pulling 2 amps would be problematic if they are not designed for high loads.

 

[Solomon Laser]

Well Soon I will be testing them for my custom build! Then I will let you know

 

[Benm]

Cool, please post back if you manage to find a supplier of any properly labeled and well performing CR2 or similarly small batteries. I have some older but nice pointers that take those - nothing really special but it would be nice to have them working reliably once again.

 

[paul1598419]

I'm not really in the market for tiny high capacity Li-ion batteries. But, I'm always looking for good high capacity batteries at a reasonable price.