Premium X battery replacement

[John Usher]

Yes, I had assumed so.

 

[John Usher]

When I say cigarette lighter charger, I'm referring to this accessory.


View attachment 7161

Yes - I know. I have that model, bought as an accessory, to replace the single outlet model which came with the device. The other port I use for my phone - if necessary - and that is slow to charge.

TomTom make much of using their chargers and USB leads (which I also use, especially when testing, to avoid any allegations of mis-use) to ensure proper performance. Personally I find this suspect - the fit of their leads, in particular, seems inferior to me.

I suspect - unless anyone can point to evidence to the contrary - that the 'Charger' (as labelled - I prefer 'PSU'), *together* with the power circuitry in the device is *only* capable of *powering* the *operation* of the device and cannot *actually* provide *any* significant power to *charge* the battery. Take it indoors and charge it up there - and that's when it works best and reliably - indoors, on the mains, and on Wi-Fi. Which is not a lot of use for a car device...

Indeed, I suspect that the battery in the device actually runs *down* in use, even when 'charging' in the car! Of course, that may depend upon the condition of the - ageing - battery.

Ironically, that is also the same as when charging on a USB-A port on a mains powered 'standard' (USB 2.0? - 5V/2.1A) to the USB-Micro port on the device, on which the limits are USB and the device, not the limitations of the car.

To avoid accusations of exceeding device limits, and potentially damaging the device, I haven't tried a higher charge rate!

Interestingly, the 'Recovery Screen' tells me I have 85% on the battery, when the Map and Guidance screens warns me after 10 minutes off power that my battery is flat! - so why the difference?

I am now trialling a modern non-TomTom 3-port 12v adapter in-car - 1 x USB-C, 2 x USB -A with up to 67W shared between the ports (well within the 120W limit on the 12V supply stated in my car manual)

My 42W max charge rate phone on USB-C to USB-C merrily tells me I am 'Superfast Charging' - no problem there, then.

I don't believe this is a 'Charger' issue - I believe it's a fundamental limit to the charging and battery configuration of the device.

I'm also experimenting with portable USB Powerbanks - 3,000 mAh upwards - to see how they work with the device when the car ignition (and the 12V supply) is off.

I'm also amused by the concept that the device should only be used on a 'charger' when the interface software allows programming in Navigation of Walking and Cycling routes, assuming that the device is running on its own battery! So is it using the same interface as on cycling devices, and these functions are irrelevant for a car device?

Did anyone at TomTom *actually* work through these 'Usability' issues when they designed these devices and interfaces? I would be astounded if they did.

 

[canderson]

@John Usher
First, rest assured that any power adapter supplied with a TomTom device will be adequate to both operate and charge the device providing the device is still within normal operating parameters. That's some pretty basic engineering, and if there was a miss there, every user of your device/charger pairing would be complaining of the same thing -- and they're not.

As for worrying about whether your USB-A charger is capable of producing 2.4A or 999A, it's irrelevant. The charge current is limited on the upside by the device being charged. It draws the current that it wishes unless it's being limited by the charge source to some lower value. You needn't worry about whether the charger can produce 1.2A, 2.4A or 5A provided it's all at 5VDC. You can make the same assumption while working with your power bank experiments.

A TomTom is primarily an in-vehicle device. While it CAN be used for walking, it's impractical for that, especially given its form factor, and battery size and weight most certainly aren't increased to accommodate an extended battery-only experience. For walking, something smaller in the way of a handheld is more practical both for handling and battery life. Their screens and lack of traffic data and spoken directional prompts typically make them poor choices for in-vehicle use. Each has its purpose. Many of us own both rather than complaining about the utility of either.

As for your 85%, you need to think about what that actually means. Using the battery voltage, it is approximating that the battery is presently at about 85% of capacity. But 85% of what capacity? That of a new battery, or that of your used one that has been charged and discharged many times, in the horrible battery environment of a vehicle windscreen? If you have spent any time using a notebook/laptop device, you'll discover that capacity decreases over time in exactly the same way, but windscreen mounted devices get much more brutal treatment. The only way to "fix" that on a the more intelligent notebook/laptop devices is to run it through at test discharge/charge cycle, and then it can give you a better idea, in units of time, not % capacity, of how long you have to go on the current charge of the battery. It does this by looking at battery voltage, but considers it against a de-rated battery capacity as discovered during the test.

Welcome to the wonders of engineering power sources for mobile devices. Above was just the tip of the iceberg. We could discuss why there are times when the device must NOT be permitted to charge while you're driving around. Now you can feel free to be astounded.

 

[John Usher]

@John Usher
First, rest assured that any power adapter supplied with a TomTom device will be adequate to both operate and charge the device providing the device is still within normal operating parameters. That's some pretty basic engineering, and if there was a miss there, every user of your device/charger pairing would be complaining of the same thing -- and they're not.

As for worrying about whether your USB-A charger is capable of producing 2.4A or 999A, it's irrelevant. The charge current is limited on the upside by the device being charged. It draws the current that it wishes unless it's being limited by the charge source to some lower value. You needn't worry about whether the charger can produce 1.2A, 2.4A or 5A provided it's all at 5VDC. You can make the same assumption while working with your power bank experiments.

A TomTom is primarily an in-vehicle device. While it CAN be used for walking, it's impractical for that, especially given its form factor, and battery size and weight most certainly aren't increased to accommodate an extended battery-only experience. For walking, something smaller in the way of a handheld is more practical both for handling and battery life. Their screens and lack of traffic data and spoken directional prompts typically make them poor choices for in-vehicle use. Each has its purpose. Many of us own both rather than complaining about the utility of either.

As for your 85%, you need to think about what that actually means. Using the battery voltage, it is approximating that the battery is presently at about 85% of capacity. But 85% of what capacity? That of a new battery, or that of your used one that has been charged and discharged many times, in the horrible battery environment of a vehicle windscreen? If you have spent any time using a notebook/laptop device, you'll discover that capacity decreases over time in exactly the same way, but windscreen mounted devices get much more brutal treatment. The only way to "fix" that on a the more intelligent notebook/laptop devices is to run it through at test discharge/charge cycle, and then it can give you a better idea, in units of time, not % capacity, of how long you have to go on the current charge of the battery. It does this by looking at battery voltage, but considers it against a de-rated battery capacity as discovered during the test.

Welcome to the wonders of engineering power sources for mobile devices. Above was just the tip of the iceberg. We could discuss why there are times when the device must NOT be permitted to charge while you're driving around. Now you can feel free to be astounded.

Thank you for your measured response.

* Chargers and device protection.

Yes, I had worked out *long* ago out that the device was probably 'Self Limiting' charging, but that's not something which TomTom states, in documentation or via Support. Probably concerned about potential warranty/liability issues.

* Walking

Yes, I use my phone for walking! The device is clearly not in a physical/power format for that!

It is, however, the sheer *absurdity* (as I see it) of having Walking/Cycling options in the navigation options in a car device which I find absurd - and confusing. Not a customer focused interface.

* 85% Battery indication and total available capacity.

You make some useful points. I have indeed periodically run the device right down and charged fully. It doesn't help.

Yes, I have many, many years experience of other portable battery-powered devices and degradation over the years. This is clearly not an 'intelligent ' device in respect of charging - e.g. 80% maximum protection on many IT recent devices.

This on a device on which, in theory, batteries are not 'Customer Replaceable', though clearly, in practice, it is possible.

I changed the batteries on an old Smart 25 (long consigned to the recycling, replaced by the Go Premium X) some years ago - it made not one bit of difference to the charge retention.

None of this is obvious to the consumer, and not helpful - and these are consumer products.

I also don't see any guidance on whether there are any battery upgrades - better battery chemistry (the world has moved on), larger capacity (mAh. 1100 packs - really?) - which are available, will fit inside the case and the onboard charge controller can manage. The replacements seem no better than the originals.

Do the latest TomTom devices (USB-C connectors) use Lithium packs? no idea, but not relevant for earlier devices.


Batteries and Charging - hmm... The 'Achilles Heel' of TomTom devices?

I draw a parallel with a lithium battery tyre inflator I had (also now recycled) - the external battery pack, unconnected, went flat in days. The battery pack in it's replacement stays charged for months! The issue lies in the quality (or otherwise) of the (invisible) cells inside the battery pack and the charging technology supplied, which one doesn't know until one buys or drills down into the reviews.

I also have current model U....n Airband receiver which takes 2 x AA Alkaline or rechargeable Ni-MH cells. The on-board charger technology for the rechargeables is antiquated, takes all day and just gets hot. An 'old but good R***o S***h external charger will charge 8 AA batteries in an hour or so, and condition them in about four hours.

The receiver works fine *all day* on standby on a 3000 mAh external power bank...

I also had a Personal Video Recorder from H****x, that was essentially a Linux box. It went wrong so frequently it went back - the support answer was always 'do a factory reset' - several times a week!!! It's much cheaper replacement from another supplier mostly works with few problems that a quick 'power off/on' won't fix.

Customer Service - hmm...

* When *not* to charge when on the move

Feel free to astound, if/when you have time.

Thanks again.

 

[canderson]

Dash temperatures, especially parked cars in the summer sun, can get bloody hot. And I mean on the order of 90C, though 60-80C is more common. Manufacturers of lithium ion batteries have set maximum allowable temperatures during charging (whether that is a function of ambient or the heat generated by charging) at around 40C. Charging at higher temperatures rapidly degrades the battery and can pose a safety risk. The lithium that plates onto the anode surface is an irreversible process, and may cause internal shorts.

Once the device on the windscreen has heat soaked for an hour or two while you're in the store shopping, it can take quite a while for it to cool down to an acceptable internal temperature for battery charging once you're mobile again.

Honestly, a windscreen is one of the lousiest places to have to park a battery operated device, and temperature monitoring of the battery pack, and using that information to make charging decisions, is critical. It's why TomTom battery packs (and many others) have more than just the + and - leads. That 3rd lead is connected to a simple temperature sensing device (negative temperature coefficient thermistor). The good news is that you don't have to worry about whether to charge - the device will see to that. The bad news is that when you start up again, you may not be charging.

I've not looked at the other end of TomTom's charging algorithm to see how they manage low temperature issues, but those can come into play as well. Normally, manufacturers don't recommend charging below 0C for similar reasons of metal plating onto the anode.

 

[John Usher]

Interesting - I had seen my old Smart 25 shut itself down when it was in the windscreen on a hot day. I *had* assumed it was a heat-related safety measure.

Slightly similar then - in some ways - to the 'Balanced Charge' on multi-cell lithium batteries and chargers, with 'C' ratings and temperature sensing for electric models.

Basically, these devices need new batteries every 2-3 years. even though they are not - officially - customer replaceable! And I still can't see any on the market (UK at least) with a higher mAh rating.

Thanks

 

[canderson]

Basically, these devices need new batteries every 2-3 years.

That depends upon the use model. If the device is only expected to operate when there's external power available (typical for most in-vehicle use), then even if the battery has degraded to the point where it will only support unpowered operation for a couple of minutes, that's more than good enough.

 

[John Usher]

I suppose that's one way to rationalise the situation!

I wonder, though, if TomTom would dare to state that in their documentation and promotional/marketing materials for their remaining vehicle navigation product line, or even dare to produce 'Next Generation' navigation devices (if any - I exclude 'TOM') with little or no battery capacity? e.g:

'If you had a built in sat-nav in your car, it wouldn't have a dedicated battery, so we're no longer providing one either - we're making life simpler for you! You know it makes sense.'

It's a thought!

Thanks!