UKC

I have had a Petzl RL, the slightly older 900 lumen version for about a year.  On Friday I plugged it in and left it until it was fully charged.  On Friday night I packed the rucksack and put the headtorch in the lid pocket, then left it in the car overnight.  The following day when I needed to walk of the plateau, it was down to one battery bar, almost dead.  As the torch hadn’t been switched on, surely it should hold its charge in cold, but not extreme temperatures?  What if you were out snow holing? Surely it should cope? 
 

Has anyone else had a problem? I am a bit concerned! 

All batteries perform less well in cold weather, and lithium-ion (which I believe the Petzl RL uses) are apparently particularly vulnerable. Temperatures don't have to be extreme to affect battery life, You appear to have left yours out in the cold for around 24 hours, so isn't surprising that it lost some charge during that period.  Whether it should have lost charge to that extent I'm not in a position to say.

For a long time the usual advice in cold weather has been to keep batteries warm, say in a pocket close to the body rather than in the rucksack.  I routinely carry spare batteries, even when I don't expect to need a torch, but spares for the RL are apparently expensive (I prefer torches which use standard AAA batteries). Or take a second torch as a backup.

Surely a mountaineering headtorch should be able to withstand relatively cold conditions for 24 hrs?  
 

I've got the same 900 one and have never had a problem. Been out snow-holing with it

I have had this issue, I keep mine in a chest pocket which seems to help it.

I’ve got a two (plus a spare battery), used them on the last two winter Spine races and not had a problem. Last year was sub-zero more or less all the time and they lasted 9-10hrs on the 100lm reactive setting.

Couple of questions/suggestions:

Are you sure the battery was fully charged? Did you turn the torch on after unplugging it and check the battery gauge? I once had a problem with an older Petzl torch where the battery charging light indicated it was fully charged but it wasn’t (one of the torches you could check charge using a phone app).

The battery power gauge might need resetting. This happened to one of mine when it was new and showed low batttery. Petzl told me to remove the battery, put in back in, fully discharge it (full power in the standard light mode), then fully charge. You might not need to bother with the discharge cycle, it worked for me just removing and replacing the battery.

If it’s neither of the above and it happens again (you can test burn time easily with the non-reactive setting), would guess your battery is knackered. If it’s only about a year old, contact Petzl, I think the battery warranty is about 300 cycles (or something like that).

I have the old one and the new one and I find the battery in the new one drains very quickly compared to the old one. Never had an issue with the cold though, so maybe it’s an individual battery thing? 

By new one do you mean the 1100L version? I have this - only using it intermittently for short times, but the battery seems to always be full without charges. Maybe it drains when used for extended periods? Also, I know lumens are subjective, but it doesn't seem as bright as i was expecting.

 All batteries work less well in the cold. How badly they will degrade on any particular occasion is probably unpredictable, but it is not surprising that one left out in the cold for 24 hours might let you down. I don't think a single incident is enough to suggest the battery is faulty.

Some older headtorches had separate battery packs on a long lead so you could keep them close to your body for warmth when in use. I haven't seen these for some time, so I guess that modern batteries are less susceptible. It's still a good idea to keep them warm until needed, and to carry spares if you might have to rely on your torch.

I have the same Swift and exactly the same problem on very cold days in Scotland. My mate with the newer version Swift reports similar. 

Around zero is OK, but it goes flat very quickly at minus 10 or colder. 

My other Petzls with Core batteries, my BD with equivalent Li battery and my Exposure do not suffer this problem, so I use them for winter climbing. 

Shame, as the Swift is excellent otherwise!

I have the 900 version and whilst I've never noticed an issue in the cold (it's only really used for dog walks from home) my switch is a bit temperamental and it has regularly turned on whilst in a pocket or bag. I think the lock on mine is crap so I always check it before leaving the house now. 

I had a similar issue with the Swift RL. I thought that I had left the light on, but out of curiosity I took the battery off and rubbed the contacts, and replaced it - back to full bars. This has happened a couple of times, I guess the contacts are imperfectly constructed. You may have already tried this but if you haven't it is worth a go.

A mountaineering head torch should be able to withstand 24 hrs of cold, but not extreme conditions.  
 

An extra battery is extra weight, given the battery life, it may or may not be necessary.  Changing the battery in the Swift is a pain, and impossible with gloves, when cold.  
 

My climbing partner had the new 1100 swift and kept it inside overnight, used it for the walk in, then into the rucksack all day and it had enough battery left to safely walk of the hill.

Is the swift fit for purpose if it can’t cope with cold conditions? Surely Petzl test for this?

They claim it will function down to -20C.  What they cannot allow for is the conditions it is used or stored in on a particular occasion.  It is well-known that batteries may lose charge at low temperatures, and this affects all batteries including EVs and mobile phones - possibly Petzl could do more to bring this to users' attention.

Perhaps I have lower expectations than you. Rather then expecting a head torch to work perfectly in any conditions I assume that it might not. There have been too many occasions when it hasn't worked properly, and it may simply have become switched on by accident. It is disappointing that your torch lost power but not surprising in the circumstances, and I would not conclude from a single incident that the battery was faulty. However if you still have concerns then speak to Petzl.

It's extra weight, but (especially in winter) a headtorch may be safety-critical equipment, and if it lets you down for any reason the consequences will at best be difficult and at worst dangerous. To carry an extra 50g in the form of a spare battery seems a small price to pay for reassurance. If changing the battery in the field is difficult take a spare headtorch (perhaps just one between the party if you are really concerned about weight). The Petzl e+Lite is only 26g. 

You’ve had mixed responses, from people (like me) saying it works fine after long periods in sub-zero temperatures, to those saying they get poor performance in the cold.

But you saw an apparent loss of 80% of the battery capacity just from storing the battery somewhere around 0°C for less than a day, if I’ve understood your initial post correctly. I’ve never seen anything like that loss in similar conditions, whether with the Swift, other Petzl torches using Li-ion batteries or other devices (gps watches, phones etc). There’s nothing unusual about the Swift’s battery as far as I know.

Probably the best thing you can do is follow the steps Petzl (or more accurately Lyon) gave me, when my new Swift seemed to be using way more battery than the spec. Because that’s probably what they’ll tell you to do if you contact them. Whether that’s to reset the battery gauge as they told me or to improve the battery contact like another poster suggested doesn’t really matter. Then put it in your fridge for a similar time and see if it does the same. If it does, get in touch with Petzl/Lyon, via the shop you bought it from if necessary.