Power Supply and Battery

[hasiel]

My 920 battery is not charging like it used to. It now can only hold a charge for about 15-25 minutes. I suppose this means that the battery is coming to the end of its life.

Is my TomTom able to operate with a dead battery with it plugged into the cig. outlet in my car, or do I have to replace the battery.

 

[canderson]

Until you hit a full battery failure, your unit will continue to operate on the car (or home) charger. Eventually, and it could take a while yet, it may cease to power up. In that case, we recommend this https://www.tomtomforums.com/tomtom...730-920-930-battery-replacement-tutorial.html rather than ditching a perfectly good unit.

 

[hasiel]

thanks

Thanks for the good advice. I will follow your suggestion.

 

[hasiel]

Update-Battery Install -charging question?

I took the leap and installed a brand new battery in my TomTom.

I notice that TomTom doesn't say much about battery care. Just to initially charge it for 2 hours.

I trust the advice of TomTomforums.com the most, a proven track record with me. What is the best course of action?
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The place where I bought my battery says the following:
"Cordless phone batteries, Cell phone, PDA, Power Tool batteries and all devices with the chemistries below

These type of batteries can be NIMH, NiCad or Lithium Ion all of these three chemistries have similar properties when it comes to looking after them.

Initial charge- all three types of batteries should be fully charged overnight on receipt.

Charges 2-6- it is very important to fully charge the battery and then use the battery until the device says low battery. there is no need to force a discharge just use the device as normal until the battery runs low. The important thing on these 2-6 conditioning cycles is that you do not top up the battery until low.

After conditioning- the best course of action to lengthen the life of these type of batteries is to only replace the device back on the charger when the device actually needs charging. All three chemistries of batteries can be cycled around 500 times if the device was placed on the charger once every day after one use the battery would last approx 500 days if placed on the charger twice a day after use the battery would last approx 250 days. A battery does not half cycle so even if the battery was 80% charged a full cycle will be used when it is placed on charge."

 

[canderson]

Those chemistries do NOT have similar characteristics! What an odd statement!

That said, a couple of warnings about lithium ion packs...

First, they require no special conditioning. Charge it in the dock until it says that it's fully charged (if not sure, just pull out and turn on and check the indicator). Neither the home dock nor the vehicle charger discharge the battery before charging, so some of what is found in that text you mention does not apply here.

If storing for an extended period (something some do, and some never do), run it down to about 50% charge. Like other chemistries, lithium ion loses capacity just sitting. However, what is unique about lithium ion is that it loses capacity faster if it is stored at 100% charge.

Other than that, use and have fun.