Overvolting by a lot. Will it last

[VaughnA]

I've got a guy here where I work wanting me to torture test some batteries. He told me that they were 14.4 volt LiOn but seem to put out about 15.5v even under load. I'm thinking that I'll give them a try with an old 12v MR11 Halogen system that I have and see how they work overvolting. Any idea how long the bulbs will last? Will I make it out of the parking lot? It looks like probably around 10% of normal life according to a couple of places I've looked. Is anyone overvolting 12V bulbs by this much?

[acroy]

I ran a "14.8V" li-ion cell on standard 20W MR11 bulbs for a year or so. Got 20-50 hrs life... not a lot. based on past experience I would suggest overvolting by no more than around 10% or so.

[kk4df]

I've got a guy here where I work wanting me to torture test some batteries. He told me that they were 14.4 volt LiOn but seem to put out about 15.5v even under load. I'm thinking that I'll give them a try with an old 12v MR11 Halogen system that I have and see how they work overvolting. Any idea how long the bulbs will last? Will I make it out of the parking lot? It looks like probably around 10% of normal life according to a couple of places I've looked. Is anyone overvolting 12V bulbs by this much?

I run a 20W MR16 with a lithium battery. It puts out 16.4 volts with no load, and about 15.5 with a load. I've run the same bulb for over a year, about 5 hours per week. So about 250 hours and counting so far.

[Booger1]

Overvolting by 20%(Li-Ion Battery) will reduce bulb life by 90% and will make your bulb twice as bright.So if the bulb is rated at 3000 hours,you should get arout 300 hours out of it.Then you'll have to cough up the big money for another bulb!

[jeff-o]

Might be better to run two lights. Run one light at normal output, and flip on a second if you need extra light.

[VaughnA]

I think I can afford a couple of bulbs if I'm getting a Lithium Ion Battery for free! I'll just carry a spare and not worry about it. It looks like they won't work for our application at work so I may get it permanently. If that is the case I'll probably build something like an achesalot LED system using this battery.

Edit:

I found a link for the battery. It is a 14.8 that is recommended for HID and Halogen bike lights. Although still overvolting I'm pretty comfortable with this setup. I'm looking forward to tonights ride. This baby on the bars and my Dinotte 200L on my head. I may finally be able to see good enough to ride at close to normal pace.

http://www.all-battery.com/index.asp?PageAction=VIEWPROD&ProdID=1578

[VaughnA]

Might be better to run two lights. Run one light at normal output, and flip on a second if you need extra light.

That was my plan, run one and just flip to the other if it burns out. I'm running with a 6v 12w system now. This should be MUCH brighter.

[Hydrated]

...run one and just flip to the other if it burns out...

The Lightbrain Plus Dual controller will let you run two bulbs, and if you are only running one of them and it burns out... the controller will automatically fail over and light the other one for you. It has tons of other functions too... like regulated over volting and battery deep discharge protection.

[VaughnA]

I have an old marwi head with dual switches. That's what I plan on using, and I always run an LED helmet so if one burns out I can still see. I used it for 2.5 hours last night with great results. Good light and runtime. Much more light than 12v.

[ovrrdrive]

Even my tired 14.4V nicad battery is up around 15.6V when fully charged. You're golden.

I finally got a set of those Optronics lights and plan to run a 20 watt flood beside the 55 watt that comes in it. Next time it fogs I bet I'll have something for it.

[geo8rge]

If this is a project you are building consider a switch that would allow you to overvolt only when you need it.

[VaughnA]

Thanks for all the help. I'm just going to run it as is. I've wired it up to use a single 15w bulb and I'll carry a spare just in case. I'm convinced after reading a few results and riding with the overvolted system that it is the way to go. If I was building one myself from scratch and not using LEDS I'd probably go with an overvolted system. Bulb life is still acceptable and you get a lot of light for a little more weight and investement.