Battery fuse

[kenetix]

After all this reading about batteries and whatnot I was looking into the possibility of adding a fuse to my evercool boxmod with imr batteries. IMRs appear to be the safer way to go and with an added power switch and the possibility of adding a fuse to the system seems to make it safer then not....

Looks like some people are using these or similar

http://www.ebay.com/itm/5x-Radial-L...421?pt=LH_DefaultDomain_0&hash=item2a1512e99d

I seen a few posts on this but kind of hard to find or maybe I just missed the big post on it.

Last question is about low voltage. I seen some information on zener diodes I think it was called can this be ellaborated on some?

http://www.ebay.com/itm/Brand-New-5...687?pt=LH_DefaultDomain_0&hash=item3f13408b2f

Basically what I am trying to do is have a fuse for the high end and protection for the low end of the battery to prevent issues with batteries. Not a fan of a plastic box blowing up in my face.

 

[CraigHB]

Those are pretty big. You can get much smaller ones for a similar price like this.

Buck and standard regulators usually have input current limiting so a fuse is not so imperative. Though, it's never a bad idea to back up the short circuit protection with Li-Ion batteries.

What do you need the Zener diode for?

 

[kenetix]

I read the zener diode was being used for low voltage cut off. When your batteries get to a low point and need to be recharged it would not allow over discharge or so is my understanding.

 

[CraigHB]

Oh, okay, for the enable pin on the regulator. I thought the TI modules cut out at a good voltage for that. They don't?

 

[kenetix]

I'm not to sure that is why I was asking for someone to ellaborate on it

 

[CraigHB]

I looked at the PTR08060W data sheet. Under-voltage lockout is 4.5V which would be 2.25V per battery, a little low for a Li-Ion. Probably okay, but you normally want to shut them down closer to 3V to minimize wear. A zener and resistor on the enable pin would probably work. I haven't done that myself since I only use boosters. I use a circuit with a voltage detector for over-discharge protection. Hopefully someone can come along and give you some advice on that.