Battery Safety Concerns

[MrLaze]

Hello,

I recently acquired a new Nitecore "Intellicharger NEW i2" to charge my AW IMR 18350 batteries. As I was reading the Nitecore user manual, I came across a warning that reads "Do not use a 4.2V/4.3V Lithium battery when its voltage is lower than 2.8V, otherwise it can be over-discharged, and/or prone to explosion at next charging."

How will I know when my batteries have reached this voltage? Will my laser stop working at this point?

I'm sorry if this is a n00b question or in the wrong forum. I tried searching for a thread that discussed this issue but was unable to find one. Thanks in advance for your help!

 

[Deleted member 46822]

First get yourself a Multi Meter, way cheaper than you think and probably free with a coupon if you have or know of "Harbor Freight Tools" in your area. This is pretty much a needed in this hobby.
At 2.8V yes your laser shouldn't work and you will probably know just like you know your TV remote is dead.
If you ordered new batteries they should not or will not come dead. Keep an eye on them with your meter time to time after laser use.
By the way if you got an Optotronic's pointer beware of the batteries you use....They don't take rechargebles like your Sanwu.

 

[Rivem]

I'm just conservative and check them after I'm done in the devices I know can over discharge them. If you get protected cells, they'll cut out before they can be discharged below that level.

Do get a meter if you don't have one though. They're very useful in electronics-related hobbies like this.

 

[Cyparagon]

How will I know when my batteries have reached this voltage? Will my laser stop working at this point?

That REALLY depends on what laser.

 

[MrLaze]

First get yourself a Multi Meter, way cheaper than you think and probably free with a coupon if you have or know of "Harbor Freight Tools" in your area. This is pretty much a needed in this hobby.
At 2.8V yes your laser shouldn't work and you will probably know just like you know your TV remote is dead.
If you ordered new batteries they should not or will not come dead. Keep an eye on them with your meter time to time after laser use.
By the way if you got an Optotronic's pointer beware of the batteries you use....They don't take rechargebles like your Sanwu.

My dad has a multi-meter. I borrowed it and used it to check the batteries. They shipped at ~3.7V DC, which is the nominal voltage, so I guess I'm set there. My Sanwu hasn't shipped yet, so my batteries won't get any use for at least another week or two. I read that it's best to store batteries at the nominal voltage and charge them up before use. :yh:

I'm just conservative and check them after I'm done in the devices I know can over discharge them. If you get protected cells, they'll cut out before they can be discharged below that level.

Do get a meter if you don't have one though. They're very useful in electronics-related hobbies like this.

I didn't order protected cells because the Sanwu website indicated that they would not fit into the Challenger II. I guess I'll just have to check the batteries every now and again. :takeit:

That REALLY depends on what laser.

What are the guidelines for this? i.e. how will I know if my laser will stop working once the batteries are at the minimum safe level? I'm assuming, based on your post, this is something that has to be determined on a case-by-case basis. What test(s) can I perform to find out whether my laser will cut off when the batteries are "dead"? :thinking:

 

[Deleted member 46822]

Why are you so worried? Is it because you think you will ruin a battery by to much discharge?
Once you start using your lasers you will pickup on how much each one of your units draws by each use. This is of course by checking them someone frequent in the beggining and at $5 for a ok meter you can get your own.

 

[Seoul_lasers]

This is why using protected cells is a very good idea. Unprotected cells can be over discharged and rupture explosively especially if they are deep cycled ( used on a high load situation) and then recharged.

Not all cells are created equal and there are quite a few poorly manufactured, even fake batteries in circulation.

 

[Crazlaser]

I've hardly ever had problems with batteries over discharging. If they do it's usually because I didn't use them for a long time. Just don't let them sit if your laser starts to dim. They're not that expensive to replace every now and then (1 or 2 every five months.)

 

[Cyparagon]

What test(s) can I perform to find out whether my laser will cut off when the batteries are "dead"? :thinking:

Use a bench power supply to vary the input voltage. The voltage where the laser begins to dim shows you the minimum operating voltage, and the voltage where the input drops to zero shows the potential voltage the cells would be at if you left the laser on indefinitely.

However, if you're like most people here, you'll consider a $400 pointer a worthwhile investment, but a decent $100 universal PSU is out of the question