My understanding is, from what I have read, is the batteries are NOT interchangable.
The 760 is a 3.7 volt, 1250mAh battery, where the 660 is a 3.7 volt, 1500mAh battery.
I think you may have a hard time claiming any damages by attempting this interchange.
What I was trying to achieve was a longer usage time on battery alone. My thinking is that the higher the mAh the longer the time to draw off the current, voltage being constant. The unit should consume the same amount of energy on a given task but have a bigger store to draw from. But I have been wrong before and probably will be in the future and this is a good way for us all to learn.
The batteries are interchangable. But i have had a few issues trying the two wire batteries in the three wire system. The third wire is a charge sense, (heat and cell condition). I changed mine over and it worked for a while, then one day the battery overheated and quit working. After replacing the battery with the old one I noticed one was L-Ion and the other was Li-PO, LI-PO was the three wire one.
Okay now with the odd fact, a 3.7V Li-PO should not need the third wire as it is only one cell, radio control aircraft use 2c 3c and larger and need the extra wire to allow for a balanced charge. So I tried three other suppliers batteries and had limited success with various brands some two and some three.
I recommend you get the three wire battery as the aftermarket ones with three tend to work well, though seem to die off after a year of use.
With all the talking and advice of swapping different batteries, using or not a 3rd wire, Li-PO or batteries from different models etc. does anyone know how much it would cost to simply send the gadget to Garmin and replace old for a new battery as recommended and done by the professionals?
After all (AFAIK) those batteries have limits like everything else.
In case of 760 I think it's about a 1000 cycles (charge/discharge=use) after that it is a throw away thing.
How much is a genuine replacement battery for 760?
Maybe, just maybe it pays to put something good which will last you 3-4years....
Elikandme for your info.
Been a while since we posted on this subject, so i thought I'd bring you up to date.Those batteries are still available online. Simple search on "Battery for nuvi 760" will take you straight there. The part no is 361-00019-11 and they are currently selling at Aus $7.92 +$1.92 postage. Fitted mine back in August 2010,is used everyday and had no problems.
Seek and ye shall find.
My 765 is now 3 years old and the battery only lasts about 10 minutes before dying, but, having said that, I couldn't care less as it is used it the car all the time and uses external power supply and works as usual.
Will check out the link though and see if the cheapy is still available
I've changed a few Garmin battery's over the yrs and found that there's not that much difference in pricing. But the ones from US seem to be better quality compared to Chinese.
Also with them I got a disk and a tool with instructions.
3 yrs now for last one (760 model) and still running sweet