1 battery or 2 batteries configuration for laser?

[QiQi]

Hi
i wanted to ask what is the best and what advantages/disadvantages is for a laser with the option for having:

2 x 18350 batteries
or
1 x 18650 battery

will the 2x18350 batteries will give me more power?

the lasers are 1W 520nm and 4W 470nm if that would make a difference

thank you in advance

 

[Alaskan]

For laser pointers:

2 x in series produces twice the voltage, that's a big difference. More power? You mean from the device it's powering, like a diode? Probably not, if the current demand isn't too high and they match the driver voltage capabilities and requirements, you can use either two or one.

 

[Encap]

Hi
i wanted to ask what is the best and what advantages/disadvantages is for a laser with the option for having:

2 x 18350 batteries
or
1 x 18650 battery

will the 2x18350 batteries will give me more power?

the lasers are 1W 520nm and 4W 470nm if that would make a difference

thank you in advance

Please make a Welcome post in the Welcome sub-forum and indicate something about yourself and you location.

More power meaning what?

In the meantime you can read this thread from 18 May 2018 which asks almost the exact same question , see: https://laserpointerforums.com/f67/single-double-batteries-my-sanwu-challenger-ii-520nm-1w-laser-pointer-102863.html#post1531342

 

[QiQi]

hi thanks for quick response
what will twice the voltage do? (sorry for dumb question)
so after reading your post i think 1 x 18650 battery will be the better option?

 

[QiQi]

Please make a Welcome post in the Welcome sub-forum and indicate something about yourself and you location.

More power meaning what?

In the meantime you can read this thread from 18 May 2018 which asks almost the exact same question , see: https://laserpointerforums.com/f67/single-double-batteries-my-sanwu-challenger-ii-520nm-1w-laser-pointer-102863.html#post1531342

im sorry
i've been here since 2012 (buying groupbuys from laserbtb/skylasers) but i forgot my account information
i didn't really wanted to make a welcome post since i did that over 6 years ago
thank you

 

[Alaskan]

Twice the voltage can burn out your pointer, if it wasn't designed for that. Other than that, unless you need it, the only thing I can think it will do (for the common drivers used today) is allow the batteries to run down further before the diode quits, assuming you are not using a boost driver.

 

[Encap]

im sorry
i've been here since 2012 (buying groupbuys from laserbtb/skylasers) but i forgot my account information
i didn't really wanted to make a welcome post since i did that over 6 years ago
thank you

You better PM a Moderator and get that situation sorted out.
Ask that one or the other account be deleted.
Having multiple accounts is a ban level violation of LPF rules/regulations.

How would anyone guess/know you made a Welcome post 6 years ago under a different name and that since 2012 in 6 years you do not yet know about laser battery requirements or how to use the LPF Custom Search at the bottom of the page to search the question on the LPF database and not to make multiple/double or back to back posts?

 

[Alaskan]

QiQi, he is right, is that other account lost to you now due to a email problem?

I edited my first post, I got off in the wrong direction with the battery diameters and lengths.

 

[QiQi]

Hey Alaskan i have no idea but it doesn't matter
Thanks you are a great help

 

[Lifetime17]

Hi Q,
For those diodes ..
2X 18350's
OR
2X18650's

2X 18650's are my first choice for those builds ..

Sorry a little late..

Rich

 

[Benm]

Given the option with all else equal i'd go for the single 18650 cell, it has more power density per volume than 2 18350 cells in series, but more importantly, you don't have to worry about the cells getting unbalanced on discharge.

With most host designs you don't have access to the 'midpoint' where the two batteries connect to eachother, so you cannot effectively use under-voltage protection. You could 'see' a total voltage of say 7 volts with one being at 4.1 and the other at 2.9. Now 3.5 volts per cell is low, but usually hard cutoff is at 3.0 v/cell.

So for most green/blue/violet lasers it would make sense to go for a single cell and boost driver.

For red diodes it can be tricky as their required voltage is very close to the single cell voltage, and you'd either need a sepic driver, or use 2 cells in series and use a buck regulator.

For IR pump diodes and such you can use a single cell with buck regulation, or even linear just fine.

 

[Lifetime17]

Hi Q,
basically keep you batteries charged for optimum performance , Eoithe 2X18350's or 2X18650's for those two diodes you wanting to build with..

Rich

 

[paul1598419]

It really depends on the driver. If it is a boost driver, you must keep the input voltage below the diode's forward voltage. With a linear driver, you won't get more power out of two batteries over one, if you can make due with one. A buck driver will, however, give you more power with two batteries in series. So, as you can see, .........it depends.

 

[QiQi]

thanks for all the good info guys
i don't know what driver it's going to be because im going to buy them from sanwu

1W 520nm - 4W 470nm - 1W 635nm

anyone have these sanwu lasers with more info on the driver?

 

[JimK]

Not sure how much more simple that can get..
Read their website specification on what batteries to use..

If you try to use more than specified, be prepared for a dead laser.

 

[Lifetime17]

Hi,
If you want info on Samwu lasers contact Bob Mac he is the Sanwu Guru here on LPF. He has a Sanwu crystal ball knows all see's all..

Rich