Of course what they really mean is that lithium batteries don't have the internal resistance that alkaline ones do, which they rely upon to limit the current in their unregulated LEDs. Not a problem for a regulated LED torch (eg some of those made by Princeton Tech), but given Petzl don't make a regulated LED I suppose it's understandable for them to forget some other companies do!

For the record I have owned a Tikka, a Tikka Plus and now a Tikka XP, so I am still a fan of these, but they could be so much better if they were regulated!

Oh dear! I bought a Petzl Tikka XP a couple of weeks ago and used Energiser Lithium batteries with it. Maybe I should have read the instructions.......

It would help if Petzl were a little more forthcoming about exactly what effect this has - a piece of lab research could be very different from the practical effect in the real world. For example if it shortens LED life by 5% or 10% if left on constantly then frankly, who cares? But if it reduces it by 50% when used in short bursts then I'd be more concerned.

As it is, I've used a variety of LED torches from Petzl and Black Diamond with lithium batteries for several years now and not encountered any issues, so I think I'll continue - I like the lithiums' light weight, cold weather performance, and longer life (especially when used with my LED/Halogen headtorch), and to be honest the rate LED technology is advancing by the time a torch packs up there's going to be something miles better to replace it with anyway!!

Edit: I may well take a look at Princeton Tec next time I'm in the market though - cheers Chris.

I've not looked at the electronics of the Petzl, but I'd guess that if there's no current limiting to the LEDs then there could be a problem.

The addition of a simple low value (and VERY low cost!) resistor in series with the LEDs would probably sort the problem. IMHO it's a very bad designer who connects LEDs straight to a battery without any current limiting, there really is no excuse for it.

If your LEDs do pack up (unlikely, they're horribly reliable) replacement white LEDs are now available quite cheaply. If anyone needs any please let me know.

John

I'll see if I can get some more detailed information from Petzl.

Hello

I have read these comments with interest and wanted to flag up some important points to you about the use of Lithium in headtorches.

The statement on the Petzl website claims that lithium batteries have a higher output during discharge which can cause the lamp to overheat. In a device Lithium batteries put out the same amount of power as regular batteries - the technology just allows the battery to do it for longer.

We have not seen any technical evidence to support Petzl’s claim and we have had no other issues or complaints regarding the performance of Energizer Ultimate Lithium in headtorches.

Energizer Ultimate Lithium performs extremely well in extreme temperatures (below 0 degrees), giving a better performance to users of headtorches in cold conditions. Lithium batteries are often best known for their performance in high-drain devices such as digital cameras and MP3 players, but also in high performance torches.

Below are a few key points about Energizer Ultimate Lithium.
Energizer Ultimate Lithium
- Performs well in extreme temperatures (from -40°C to +60°C)
- 33% lighter than alkaline AA
- The world’s longest lasting AA battery in high-tech devices
- Lasts up to 7 X longer in digital cameras*
- Takes up to 630 pictures** in a digital camera vs 90 photos with an alkaline battery
- Carries a 15 year shelf life
- Lasts up to 5.5 hours longer than leading ordinary alkaline batteries in MP3 players
- Up to 12 CD player hours
* Based upon ordinary alkaline in proposed industry testing. Results may vary by camera
** NCIEC digital camera test, results may vary by camera


Elizabeth McGregor
Marketing Director
Energizer UK

I have to say that whilst we must appreciate the efforts of the last poster, she does represent a company with a product to sell, so the old adage could be used here, "well they would say that wouldn't they."

You cannot simply dismiss the "research" by Petzl, what do they have to gain by scaremongering?

They do not manufacture or sell batteries or as far as I am aware, do not have vested interests in a battery manufacturer.

I do think though that the risk is minimal and long term, and as Matt says, LED technology is advancing in leaps and bounds and will soon make 'current' (pun intended) technologies absolute.

I have just purchased a new caving/mining lamp that uses a focused bright white LED and it is superb, It too uses a LI rechargeable battery pack, but it does have a regulated assembly within the headset.

some time ago i decided lithium was the way to go and replaced both my black diamond headtorches both LED.Also my cateye mountain bike el 800. All work well bright dont seem to get any hotter and last sooooo much longer. All the best to you all.

Never seen / heard of a problem with using Lithium batteries with LED's myself - but there again Petzl don't sell batteries but really they *should* have put in a regulator so you can use *all* battery types.

Lithium are great for their lighter weight and greater capacity!