Gps Power Source

[+nerys]

Maha chargers rock. :-) have have some amasing radioshack of all things chargers. 8 cells intelligent fast charger (2-3 hours tops) Great charger

 

I used to have around 100-120 AA nimhs (i the past my cameras took AA's so I ate a lot of AA cells)

 

I have since gotten rid of all of them and now use 15min exclusively. I have 4 of these chargers so I can charge 16 cells - I hate waiting :-) and best of all I can use them in more gadgets now. in the past I would not use rech in my single cell gadgets since you had to charge in PAIRS and I would lose the dead one before I killed a second one.

 

the 15min chargers can charge EACH CELL individually so now I can charge just 1 battery if I need to and on top of that I can assymetrically charge my batteries I can put in a dead cell nearly full cell and 2 half charged cells and it will charge EACH properly to full charge.

 

just awesome ! I cant wait till the low self discharge cells come out especially if they can do them in 15min varieties !! the LAST remaining con to nimhs will be gone then !! :-)

 

Chris Taylor

http://www.nerys.com/

[+Lone Duck]

Rechargables for things that you use often. Alkalines for long term storage, or if you like to spend time in lin buying batteries.

[lostinthewoods]

Heat in general is damaging to NIMH and LITHIUM batteries there chemistries dont like it (Lithium being MUCH more sensitive to it)

I've not heard of this, before. I can do some research and see what I come up with, though.

 

The temperature of a cell is directly related to it's self discharge rate, but that only discharges a cell, it does no long term damage. If you were to charge a cell in a nice cool room, take it out in the mid-day sun in the desert and put it in a black box, it would discharge quite quickly--cell phones in hot cars have been reported to run down in

a day. But, if you took it back into the cool room, you could recharge it and it would be in as good of condition as a cell which had been discharged in the cool room.

 

All of that is assuming you don't take the cell temp into the 'boil off' temperature range of the cell. If you do that, you can kill *any* kind of cell which has electrolyte in it. Because, hey, it's a liquid, it'll boil at some point. And, once it's gone, yeah, the cell won't work any more.

 

Is that what you meant?

[+nerys]

No I meant just what you implied - if you take it out in the desert sun and use it the overall life of the battery will be shortened compared to someone who uses it in cooler temperatures.

 

Example. 2 people with the same lets say CD Player (older higher drain CD player) with the same CD inside.

 

one in the sahara one in Pennsylvania in fall or spring.

 

each charged and they plays CD till it dies repeat

 

at some point these cells will die and become effectively useless

 

this will happen much sooner to the cells being used in the sahara.

 

its much much worse for lithium cells.

 

Chris Taylor

http://www.nerys.com/

[OttoLund]

Choose NiMH rechargable batteries, the best for the GPSr, MP3 players, digital cameras etc.

For my Garmin GPSmap 60CS GPSr I circulate 8 batteries. The batteries lasts for approximately 5 years and can be recharged 500-1000 times. After a lot of research in this and other forums I came up with the report Choice of batteries for different purposes.

 

I like the NiMH solution because it's relatively cheap, the batteries have excellent characteristics and produces little and nonpolution waste, for my GPSr only 8 batteries per 5 years. With alkaline batteries I would have used over 500 batteries in a 5 years period

Edited February 6, 2006 by OttoLund

[lostinthewoods]

No I meant just what you implied - if you take it out in the desert sun and use it the overall life of the battery will be shortened compared to someone who uses it in cooler temperatures.

 

Example. 2 people with the same lets say CD Player (older higher drain CD player) with the same CD inside.

 

one in the sahara one in Pennsylvania in fall or spring.

 

each charged and they plays CD till it dies repeat

 

at some point these cells will die and become effectively useless

 

this will happen much sooner to the cells being used in the sahara.

 

its much much worse for lithium cells.

 

I see only one possibly thing that can reconcile out differences. That is the fact that operating at higher temperatures will increase the internal cell resistance and result in lower *apparent* cell capacity. Thus, each charge/discharge cycle results in fewer minutes of use--worse for higher discharge devices than for low discharge ones. This means that in, say, 6 months of continuous use, the cells in the hot environment will have been cycled more times than those in the cold environment. Thus, the hot environment cells will hit their cyclic charge limit sooner than those used in the cold environment.

 

Does this agree with you?

[albertkircher]

In response to the OP, I would recommend NiMH for everday use and Lithium for extended outdoor trips. I'm not sure what happened with your unit, but Lithium should work fine.

 

AA NiMH vs. alkaline vs. Lithium

 

Having used different electronic gear for some years now, I reccomend the following:

1) NiMH rechargeable batteries as standard, in the long run the chapest solution. The charger should not charge too fast, since the batteries will get hot and the lifetime will be reduced. Get yourself 2 sets of NiMH and a good overnight charger, then you will be able to use the batteries even for some years. 15 minute chargers tend to reduce the lifetime of the NiMH batteries.

2) Simple (cheap) alkaline batteries if you are out somewhere without possibility to recharge the NiMH batteries.

3) Lithium batteries only if you are out on a trip in very cold conditions. For example a dogsledge tour in northern Sweden, or winter camping in cold Canada. In my opinion this is the only area where Lithium cells are appropriate.

 

Greetings,

AK