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View Full Version : Issue with using Lithium batteries in DTS tracker


skiyak777
11-26-2005, 07:25 PM
A few weeks ago while doing a beacon practice session, I noticed my DTS Tracker was not working properly in search mode. While it would transmit fine and could be picked up by other beacons, in search mode it would not give any indication of direction and gave a constant reading of 0.1 M. Normally when I put my beacon on I simply check to see whether it transmits and receives, not whether it searches correctly, so I don’t know how long I’ve been using it like this. I returned it to REI and they gave me another one.

Turns out that the problem appears to be related to the use of Energizer Lithium AAA batteries. When I initially used the new beacon with the alkaline batteries supplied with it, it worked fine. Today when I changed to Lithium batteries, it ceased searching again. I also tried this with a 3rd beacon with the same result. Switching back to alkaline batteries rectifies the problem. Cursory examination of the batteries with a voltmeter shows they both put out the correct voltage, so I’m not sure what the problem is, but in any case I would advise against using Lithium batteries in your tracker (even though I love them in cold weather for other devices.)

Sledhaulingmedic
11-27-2005, 10:08 AM
I've had problems with lithium batteries before, with a variety of devices. (The Xenon bulbs in Pelican lights, for example burn out.)

I believe that Static voltage across the terminals is higher than what shows under load. (A voltmeter is a load, although a very high impeadance one). The result is a voltage spike when you turn the device on. This could burn out the Xenon bulb and could lock up the circuitry in the beacon.

I just stick with alkalyne. (Besides, the lithium are still outragously expensive.)

PWDR8S
11-27-2005, 02:32 PM
I've had those lithium batteries overheat on occassion. I used them in my former FujiFlim digicam and one night after shooting a Coffeehouse session I felt my cam getting very very warm through my pocket. I then pulled it out and it was almost too hot to touch. I immediately removed the batteries and they were way too hot to handle with bare flesh. I've been leery of them since. I've heard that this happens sometimes but I'm really curious as to how often AND what equipment NOT to use them in.

Tommy T
12-25-2005, 09:08 PM
I seem to recall that Ortovox, as part of its singlehanded assault on the battery industry's lack of standards, has had some bad things to say about lithium batteries. Can't find the press release right now, though.

Tommy T.

NtrentT
12-27-2005, 01:52 AM
Might have the the correct voltage, but not the correct current.

Check the Amps and see if they are the same.

Sledhaulingmedic
12-27-2005, 09:23 AM
Batteries are not rated in Amps as the current will depend on the total resistance of the load, as well as the internal resistance of the battery. (The exception are automotive lead acid batteries, which are, for all intents and purposes, flowing into a short circuit when turning over an engine.)

Rechargable batteries are rated not in Amps but in AmpHours. (Most anything you'd want to carry would be in milliAmpHours). This is not the current it can deliver, but rather it's capacity: how long it can deliver current at the rated voltage. For example, a 400mAH NiCad battery could deliver 1 milliamp for 400 hours (say power a small LED). Or, it could deliver 400 Milliamps for an hour. (Like powering a handheld radio in transmitt.)

The problem with Lithium batteries is not their Voltage or capacity, but rather some more complex characteristics of their chemistry.