Welcome to Laser Pointer Forums - discuss green laser pointers, blue laser pointers, and all types of lasers

LPF Donation via Stripe | LPF Donation - Other Methods

Links below open in new window

ArcticMyst Security by Avery

<<Battery Issues, Need Help!>>

Joined
Oct 1, 2016
Messages
148
Points
18
Hey everyone, so I just purchased the Thor MII 1.4W 445nm Laser (here) along with 6X GTL 16340 batteries (here). The main reason I bought this laser was to see first hand what the 445nm wavelength looks like hoping I could decide which wavelength of blue to get for my PL-E Pro (445nm or 465nm). Anyway, since this laser was purchased for test reasons only and the fact that this is going to be the only laser I will have which will require 16340s I didn't feel like spending much on batteries. So I received the laser a few days ago and got the batteries today. I charged all the battery to 100% using my NiteCore D4 charger and then I popped two batteries into the laser, turned it on and experimented with everything for a little bit while making sure not to keep the laser on for too long. So after about 2 minutes of use the lasers output turned into almost nothing. I shut the laser off for about 20 seconds and turned it back and it was near full brightness again and then after like 15 second it fell to almost nothing again. I took the batteries out and put them on the charger and one read 2.73V and the other read 3.88V. After about 10 seconds the 2.73V jumped to 3.4V and then 3.8V another 10 seconds later. The other battery went from 3.88V to 4.06V within 10 seconds as well. This voltage behavior seems to be apparent in the laser which explains the laser's vastly varying power outputs. This problem has happen several time now with all 6 batteries. Before I contact the seller about these batteries I'd like to know your guys' opinion on whats causing this issue.

Before anyone mentions it, yes I am aware these are cheap batteries. I bought these since they are for a testing laser only. I thought only the capacity and amp ratings on cheap batteries were off; I had no idea their voltage stability would suffer as well....if that's even the case here.
 
Last edited:





Sta

0
Joined
Jan 27, 2014
Messages
1,737
Points
83
GTL batteries are worse than Ultrafire, that is how bad they are.
Throw them out or destroy them immediately; they are a danger to you, and are not reliable in any way - capacity, current draw, or voltage.

I recommend purchasing some Efest 16340s or another reliable company. You will not regret it.
 
Last edited:
Joined
Oct 1, 2016
Messages
148
Points
18
Haha damn that's pretty bad; so you think the voltage behavior is due to the quality of the batteries? Will I not experience this behavior with other 16340s?
 
Last edited:

Sta

0
Joined
Jan 27, 2014
Messages
1,737
Points
83
Re: Proper 16340 Batteries for my 445nm 4W Laser

Haha damn that's pretty bad; so you think the voltage behavior is due to the quality of the batteries? Will I not experience this behavior with other 16340s?

Btw we are talking about 16340 batteries here, not 18650 batteries.

It may be the quality of the batteries, or that they are being charged faster than rated (these low-quality cells should NEVER be charged quickly.) Charging too quickly may lead to a voltage drop, which would explain what you are seeing.

This is also dangerous because a voltage drop in the battery could lead to overcharging, then explosion. If a LiPo bursts, you get some flames. If a Li-ion - like your 16340s - bursts, you get a loud BANG with shrapnel and potentially toxic material everywhere.

Better quality 16340s will not experience these problems.
 
Joined
Oct 1, 2016
Messages
148
Points
18
Thank you Sta, and yes I am aware of the dangers of batteries, that is why I was so surprised that everyone here recommends high drain batteries with no protection....
Btw the NiteCore chargers are as safe as chargers get and they have every protection you could ask for from a charger so I feel safe as far as charging goes, but not draining.

What are some good 16340 batteries besides efest?
 
Last edited:

Sta

0
Joined
Jan 27, 2014
Messages
1,737
Points
83
Re: Proper 16340 Batteries for my 445nm 4W Laser

Thank you Sta, and yes I am aware of the dangers of batteries, that is why I was so surprised that everyone here recommends high drain batteries with no protection....

What are some good 16340 batteries besides efest?

You may want to look at the battery tests on lygte-info.dk -- it is THE best website for detailed battery information. I don't know any specifics off the top of my head but if you go there you will find some good brands.
 
Joined
Oct 1, 2016
Messages
148
Points
18
Re: Proper 16340 Batteries for my 445nm 4W Laser

Yeah Ive seen that website many times. I even looked at that site for these batteries but I already knew the capacity was no where near what was printed on the batteries. I thought they would be like 1400mAh like alot of non high drain batteries are, but again I had no idea the voltage stability suffers from low qualty batteries.
 
Joined
May 12, 2013
Messages
751
Points
43
Re: Proper 16340 Batteries for my 445nm 4W Laser

I thought only the capacity and amp ratings on cheap batteries were off; I had no idea their voltage stability would suffer as well....if that's even the case here.

Capacity and amp discharge characteristics are directly related to voltage and internal resistance. No doubt those batteries
have such low capacity and such high internal resistance that the voltage drops extremely quickly even under light loads.

I thought they would be like 1400mAh like alot of non high drain batteries are, but again I had no idea the voltage stability suffers from low qualty batteries.

At best those batteries are 500mAh or less.
 
Joined
Oct 1, 2016
Messages
148
Points
18
Re: Proper 16340 Batteries for my 445nm 4W Laser

The best 16340s? Hmm I've read a couple articles/forum threads of people saying they can up to 1400mAh, but 1000mAh seems more realistic to me.

Anyway, I just did a bit of research and saw a pretty good test for the Efest 16340s 550mAh but unfortunately they are discontinued pretty much everywhere unless I wanted to pay a huge premium for them on Ebay so I went with the Efest 700mAh and those look to be the new 550mAh batteries that were discontinued.
 
Joined
Oct 1, 2016
Messages
148
Points
18
Idk if this matters, but I just noticed that every time I put 2 16340 GTL batteries in this laser and after about 5 minutes of use one is always at 2.7V and the other is at 3.9V....I'm concerned that this laser is draining one battery way fast than the other and it may not be a bettery problem...
This same thing happens no matter what 2 batteries I use.
 
Joined
May 12, 2013
Messages
751
Points
43
I'm concerned that this laser is draining one battery way fast than the other and it may not be a bettery problem...
This same thing happens no matter what 2 batteries I use.

It's almost certain that it is due to the batteries. Since they are of low quality each cell has a different internal resistance and a different capacity.
Thus each battery gets depleted at a different rate. You should not have this problem with quality cells with matched capacities.

Notice how each discharge graph on the website that Sta linked to has two discharge curves on the one graph, this is to assess whether a pair of
identical cells has identical capacity. If two batteries don't have similar discharge curves then they are unsuitable for use in a series configuration.
 
Last edited:
  • Like
Reactions: GSS
Joined
Oct 1, 2016
Messages
148
Points
18
Thats too unlikely to be the case...Im aware these are shit batteries but I have 6 batteries an no matter which 2 I choose one will always drop to 2.7V and the other will drop to 3.9V within 5 minutes....there is no way that i just happen to choose 1 3.9V battery and one 2.7V battery every time i choose 2 batteries. Something else is going on here.
 
Joined
Aug 23, 2016
Messages
259
Points
28
maybe it has something to do with the driver or something? idek as im not all that educated in the world of lasers and electronics
 

joeyss

2
Joined
Jul 23, 2008
Messages
1,112
Points
0
Thats too unlikely to be the case...Im aware these are shit batteries but I have 6 batteries an no matter which 2 I choose one will always drop to 2.7V and the other will drop to 3.9V within 5 minutes....there is no way that i just happen to choose 1 3.9V battery and one 2.7V battery every time i choose 2 batteries. Something else is going on here.

i pray it's not a lose connection to the driver thats drawing current do they feel warm? one warmer than the other?
 




Top