AA batteries vs Lithium Ion

[+GeoBroke]

We have an older Magellan Sport Track Pro GPS unit and are thinking upgrading. I see that a lot of new models use Lithium Ion batteries, but there are a few new ones that still use AAs. What is the overall consensus on the battery issue?

[+user13371]

There is no consensus.

 

AA batteries, disposable or rechargeable, are readily available, inexpensive, and easily swapped out in the field. To some users this trumps any perceived advantage of lithium-ion, which are by comparison more expensive and harder to replace.

 

Lithium ion rechargables -- if your device supports them -- can usually be recharged without removing them from the GPS (e.g., while plugged into your computer, a wall-outlet, or the cig-lighter in your car). To some users this trumps any perceived advantage of AA.

 

Your best choice depends on your own usage pattern.

[+grateful cacher]

My experience with alkaline AA batteries was that the backlight and sounds on my Oregon GPS would fade when they reached 50% of the battery indicator. Sometimes that would be only a few hours. With Lithium Ion, I can go several hours and the backlight and sounds last till the indicator is in the red. They last longer as well. True they are more expensive initially, but with the ability to recharge them, and how long they last, they are cheaper than alkaline. I got a charger and 4 batteries for $12, and then an extra set of batteries for $7. I carry two in the GPS and two spare sets and that will last me a couple of excursions. Your mileage may vary but for me it lithium all the way.

[Wanthuyr Filho]

But don't make a confusion between Li-Ion rechargeables and those disposeable lithiums (1.5v AA form factor).

In my opinion AAs are better because you can get rechargeables (which in turn you can find of different types/advantages), that are easy to find (even in the long-term, which is a great differential) and somewhat cheap... And you can always put in alkalines (definately not good for the Oregons) and also the disposeable lithiums (excelent).

On the other hand, IMHO, the great advantage of the Li-Ions/Li-Polys is the complete lack of "memory effect" whatsoever and a much better capacity assessment (energy gauge).

[+Chrysalides]

I was going to type up a list, but think I'll just link to Wikipedia.

 

http://en.wikipedia.org/wiki/Lithium-ion_battery#Advantages

 

Lithium ion (rechargeable) is not a drop-in replacement for AA batteries. They're made up of individual cells that have a voltage of 3.7V, and the size is different. One exception is the RCR-V3 which will run on some devices designed to take CR-V3 or two AA. The 14500 is almost the same size as an AA cell, but if you put 2 into your GPSr, the 7.4V is likely to fry your device.

 

I prefer AA because NiMH is cheaper, I can exchange them between my various devices (camera flash, flashlight, P&S camera) and in an emergency, I can pop into a 7-11 and buy a pack of alkaline cells.

[+Jeep4two]

It seems that maybe there's some confusion about whether some of the posters are using Lithium Ion rechargeable cells and Nickle Metal Hydride cells. Most interchangeable AA rechargeable sold on today's market are NiMh (Nickle Metal Hydride).

 

Back to the OP - I'll echo the statements from our Corps of Engineers friend. It depends on your usage on whether most would benefit from rechargeable AA's or Alkaline AA's. However if you get a unit that has a Lithium Ion battery pack included you will be limited on your battery choices, usually having to buy packs made specifically for your unit and often not field replaceable like typical AA batteries.

 

I personally have found today's rechargeable AA NiMH batteries (2500 mAh rated) are fine for my uses (occasional caching, with plenty of notice before heading out to charge 6 or 8 extra batteries to take along in the cache bag - enough for a full weekend of caching or hiking typically).

 

I don't really like the idea of batteries getting low or dying in the field and no way to change them out.

 

The NiMH battery has advanced quite a bit as well. There are now low discharge NiMH batteries that have slightly lower mAh ratings (slightly shorter run time) but won't discharge nearly as much when not in use.

 

Search the forums for threads on the NiMH technology and you'll see lots of debates on which brand is better, whether to use regular NiMH or Low Discharge types and similar topics.

 

If you choose a unit that uses AA batteries and you go with NiMH just remember. Charge your batteries before going out and always have a spare set of alkalines for emergency use just in case. A set of plastic cases for your NiMH batteries is a good idea to keep them from shorting in a pocket, backpack or cache bag too. I picked up a set of eight 4 cell holders on evilBay for under $6.00 including shipping. Some batteries will come with holders/cases as well.