Battery pack vs AA pack

[truckinguy]

It seems to gain mAh's going to the AA battery pack is the way to go. The Gamin pack is 3.8v 3100 mAh's. Going with 3 2200NiMH rechargeable NiMH would yeild much more usable mAh's wouldn't it? or am I missing something.

[Exurban]

3.8v X 3,100 mA = 11,780 mWH

1.2v NiMH nominal voltage X 3 X 2,200 mA = 7,920 mWH

So no. The LI pack is more. Unless I need to check my math.

[Exurban]

Should have said mW, not mWH. And even if you drop the LI nominal voltage to 3.6 and bump the NiMH up to 1.25, the LI pack still has more capacity.

[GPSrChive]

It seems to gain mAh's going to the AA battery pack is the way to go. The Gamin pack is 3.8v 3100 mAh's. Going with 3 2200NiMH rechargeable NiMH would yeild much more usable mAh's wouldn't it? or am I missing something.

The Li-ion Battery pack is 3.8v @ 3100 mAh.

The AA Battery pack with three 1.2v 2600 mAh NiMH batteries would be 3.6v @ 2600 mAh. (They are in series, not parallel)

[truckinguy]

Okay thanks. Great stuff. I love the unit so far. Just did a mid week hike of 3 miles and 800 ft gain and today a 4 mile with 950ft gain. Very accurate and worked great.

[truckinguy]

What about Lithium AA's. Vapcell's are 1.5 v's. 1800 mah. 4.5v x 1800 = 8100 but these are lithium. Maybe they would give better results then NiMH AA's. For one it would be 4.5 volts instead of 3.6 volts for the NiMH.

[truckinguy]

What about Vapcell Lithium AA's. Vapcell's which shown in reviews as great cells are 1.5 v @ 1800 mah. And 2733 mWH
How would 3 of them stack up against the Garmin pack ?

[GPSrChive]

What about Lithium AA's. Vapcell's are 1.5 v's. 1800 mah. 4.5v x 1800 = 8100 but these are lithium. Maybe they would give better results then NiMH AA's. For one it would be 4.5 volts instead of 3.6 volts for the NiMH.

That is still only 1800 mAh, which is only about half of the OE Lithium battery pack capacity at 3100 mAh.

[truckinguy]

For a backup power while hiking I think I'll buy and try the aa battery pack and load it with Ladda 2450's or Panasonic Pro 2450's which seem one of the best in test's I've seen. I used them in my 680 most hikes and kept the OEM lithium for backup. I'll do the same and use the OEM Garmin Lithium pack for a back up. Being Lithium it would hold a charge for a while and work okay in cold etc.

My hikes are seldom more then 6 hrs and never have the screen light or extra options on like wireless,bluetooth,etc. I hiked 6 hrs yesterday and the OEM pack was still showing 3/4 or more full. And it was running the entire 6 hrs tracking on gps/galileo and wass on. Track point every 3 seconds.

It is just so much quicker to change the AA's for use if forgot to charge them or for an unexpected or follow up hike.

Love this unit. It is a brick but so much nicer then the 680 Montana for sure.

[GPSrChive]

I assume you have the 700, and not a 700i or 750i?

Yes, this thing is a monster, but the improvements over the previous generation Montana 6x0 far outweigh the size.

FYI - the AA Battery pack is available via the GPSrChive Store!