Note: Lithium AAs for Petzl Myo XP = Fried

Guys,
Juz to note that my friend juz 'fried' two(2)different Myo XP seperately when using them with Lithium AAs. He managed to get a exchange with his retailer for the first Myo thinking that its a lemon...as it was only two months old, but when the second Myo was 'fried' soon after as well, he figured that the circuit was probably not designed for Lithium AA.

Any of you guys out there with similar experience?

Hmm. I've used lithiums in my Myo XP without incident. I'm on my second set of batteries.

weird...

According to Thomas-Distributing:
"Eveready Guarantee : Eveready will repair or replace, at their option, any device damaged by these AA lithium batteries, if the device is sent to Eveready Battery Company."

http://thomas-distributing.com/enr-l91bp-4.htm

It is possible that if the Vf (forward Voltage) bin of the Luxeon is low (i.e. "H"), it may fry, while a higher bin like J or even better, K will do much better with lithium batteries since Lithium AA's are 1.7V versus 1.5V for alkalines. The higher the Vf, the more voltage the LED itself can take before overheating and eventually frying. It's up to the Luxeon Lottery what Vf you get if the manufacturer doesn't buy a special bin.

Petzl says:
"Use alkaline (preferred) or rechargeable batteries."
http://en.petzl.com/petzl/LampesProduits?Produit=554
See on the left of page where it says:
Technical Notice
Specific notice MYO XP
It does NOT say no lithiums.
This is serious for me, because for winter temperatures (-20F) alkalines are no good. You need to use lithiums or have a separate battery pack that you keep inside your coat. I wonder if I'm going to have this problem with my Tikka XP? AAA lithiums are too expensive to use in the summer, but I was going to use them in winter.

--Walter
PS I have emailed Petzl to ask about this issue.

My friend use it for caving & based on his account, the 1st Myo fried at the 2nd or 3rd change of batteries. I believe his 2nd Myo got fried shortly going thru' the 1st set of batteries.

We probably need to take into account the hot & humid climate we have locally...approx 35 degree celcius at time & 90+ humidity 100% of the time, but I never have any problems with other LED flashlights/headlight.

I went thru the instructions provided by Petzl & yes....Lithium was not mentioned, thus I thought that I should share the info with you guys.

BTW, my old PT Aurora (which was released prior to the avaliability of Lithium AAA by Energizer) would supports Lithium AAA & it was verified by an e-mail from PT customer service even when its not mentioned or updated on the website or instructions.

Lithium batteries (AA and AAA) are OK for the Myo XP and Tikka XP according email from Petzl.

Email from Petzl:

"Walter,
Lithium batteries can be used in the MYO XP and TIKKA XP model
headlamps. According to our tests/data these LEDs should not become
damaged with the higher voltage output from Lithium batteries.


Should anyone have problems, such as described below in the comments
from CPF, we will certainly replace their light under our warranty
program.

Let me know if you have any other questions,
Jon

Jon Rockefeller

Manager - Headlamp Division"

If anyone wants to contact him directly PM or email me and I'll send his contact info.
[email protected] works in general.

Destroid Monster: If your friend's problems haven't been fixed, have him contact Petzl and they'll replace his light.

--Walter

thanks for the info, I take it that the two headlight that my friend have are lemon then.

Destroid Monster said:

thanks for the info, I take it that the two headlight that my friend have are lemon then.

Click to expand...

Your friends 2 headlights are either lemons (bad batch) or something systematic is wrong. Maybe "approx 35 degree celcius at time & 90+ humidity 100% of the time" makes them overheat. If so, then they should fix that problem.

Did your friend get both headlights replaced? If not he should contact Petzl. Email me or PM me and I'll send you the email address.

--Walter
PS I think I'd overheat at that temp/humidity too

He managed to get the first one replace at the store he brought....not too sure about the 2nd one. Thats the problem with service support in a small country in Singapore. We are so far from the States & our market/demand is so small, we tend to be neglected.

Snowleopard, pls PM me with the e-mail address for Petzl & I try to see if my friend need it.

Is there any chance that these lights are knockoffs?

I've not heard about counterfeit flashlights, but I suppose it's always possible with a popular international brand like Petzl. FWIW my MYO XP has no problems with Li cells.

Good luck!

--Rick

Destroid Monster said:

He managed to get the first one replace at the store he brought....not too sure about the 2nd one. Thats the problem with service support in a small country in Singapore. We are so far from the States & our market/demand is so small, we tend to be neglected.

Snowleopard, pls PM me with the e-mail address for Petzl & I try to see if my friend need it.

Click to expand...

I had a thought about the myo XP, and I think that they don't have battery reversal protection system i.e. if you put the batteries in the wrong way and turn it on...then this will kill it... Iam not trying to say that your friend made a mistake, but you never know?

just an idea...

I have placed my cell wrongly before....didn't kill my unit

Some updates...https://www.candlepowerforums.com/posts/1601533#post1601533 &
some information from Petzl websites on Lithiums: http://en.petzl.com/petzl/LampesNews?News=159

I could faily conclude that both of my friends Myo's are thus not lemons.....the Myo is simply not meant for Lithiums AAs

Destroid Monster said:

Some updates...https://www.candlepowerforums.com/posts/1601533#post1601533 &
some information from Petzl websites on Lithiums: http://en.petzl.com/petzl/LampesNews?News=159

I could faily conclude that both of my friends Myo's are thus not lemons.....the Myo is simply not meant for Lithiums AAs

Click to expand...

Thanks for posting the Petzl link. There had been some conflicting information posted earlier, but this looks like the definitive word...