Here's an answer I got once when inquiring about the battery and what could affect it (to prevent any problems)
Below is some information you would like to have about your unit's battery:
- It takes about 2 hours to fully charge the GO battery.
- The battery stops charging when it's full, so, for example, you can leave it plugged in overnight.
- Leaving your TomTom GO connected all the time doesn't overcharge it.
As in any technology equipment, there are certain meassures that may help you prevent any problems in the future.
Do not expose your TomTom GO to extreme heat or extreme cold; you may permanently damage your battery's capacity, even more if you charge your GO in these temperatures.
The table below shows temperature ranges for using your TomTom GO. As you can see, cold weather may affect your batteries life.
Standard operation - 10?C (min temp) + 55?C (max temp)
Short period storage - 20?C (min temp) + 60?C (max temp)
Long period storage - 20?C (min temp) + 25?C (max temp)
You also asked about the time you can expect the battery to last when not in use. If the device was fully charged and idle, you may expect the charge to last about 6 hours.
We'd advice you to have your TomTom GO 300 in the car only while driving, since cold temperatures do shorten the battery's life. If you're not planning to use it, try to keep it as warm as possible, or take it inside your house to prevent short charge holding times.
Please keep in mind that the battery cannot be replaced, but a correct care of it would avoid any problems in the future.
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They mentioned in a phone call that the unit has a lithium battery, and as cell phones they may develop a "standard use". That is that if your battery is not constantly charged and depleted, it may get used not to hold that much of a charge, so problems may occur with it not holding a charge. But I guess that's in the long run!