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Polar M400 Battery replacement

Hy,

does anyone know how to change the battery of the M400 watch and where i can buy a new battery.

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How much can it cost to replace a charge unit in polar m400

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Hey, did anyone have a Battery for me ?

Shipment to germany? :D

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hi, been looking all over the web for spare parts for my polar m400; battery and screen module, no luck anyone any ideas?

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Hi, I have this type of activity tracker, you have two pins at the top and the bottom of the watch, holding the rubber bands and a little arrow which shows where you have to push them to remove the pins. (Push it with a little needle or paper clip to remove)

Then you can easily deattach the two bands, and have your 4 hexalobular screws exposed. Unscrew these 4 screws to remove the backplate which reveals the easily removeable rounded watch battery that can be bought in any electronics store.

Hope I could help.

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thanks for the answer. I have dismantled the watch, but am having difficulty finding a relacement for the battey. I have a EVE 3.7V 190mAh lipo battery cell (352826). Does not seem to be something the average electronics store would stock. Can you provie advice on where you sourced a replacement. Ta.

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Hi @jrejos ,

The specs that you have given for your battery, 352826, indicate that it is a 3.5mm x 28mm x 26mm dimensioned battery.

Whilst i haven't been able to find an exact replacement online I did find this battery, which while it has slightly less capacity 130mAH in lieu of your 190mAH being smaller (302323) it should fit into your watch, if you can't find anything else.

.

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Battery change would be easy if you could find a battery. A T5 star driver is needed to open the watch and the battery is stuck to the bezel, easily removed.

After many hours trying to find a battery (via AliExpress) I gave up. There are two issues:

1) The Polar battery is a lithium polymer (LiPo) 352826 that is not available. You could choose a smaller size such as a 352424, but you'll get lower mAh rating.

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2) There are leads on the 352424 and a power regulation circuit board as in the image below. The Polar battery has a bare plastic contact bar with two large contacts. You'd have to modify the power regulation circuit to remove components and leave just the contacts. I tried that modification with another battery and it seemed it would work.

If you choose the smaller battery it would cost ~ $10. I measured the case and bought a battery via AliExpress, but the vendor lied about the size; he took a battery that was approximately the size requested and stuck a label on it that said a 362927. The battery was actually 403124, far too large to fit the watch. A 362927 battery would be 3.6mm x 29mm x 27mm, with a tolerance of ~+/- 5%.

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Communication from Polar:

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We usually do not send fixed prices as the issue can be different than expected and the Tech can find something else wrong. However, at best, a battery change without tax or shipping would be $24.95.

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To start the process, please register your repair online at the link below. Include a copy of the registration or the confirmation email with your product. Include details regarding the issue(s) you are experiencing. Also it is recommended to send in the complete product set (watch, heart rate sensor, strap, cable, etc.) so that we can ensure all devices are working properly. Please include a copy of your proof of purchase.

https://service.polar.com/service/PSCSPr...

Please feel free to contact us if you need further assistance. We may be reached by E-mail, Livechat, or our toll free line by clicking on the link below.

http://www.polarusa.com/us-en/support/co...

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Regarding battery 352424, why do you think it necessary to remove the protection circuit board? From the pictures it seems that removing the yellow plastic and exposing the connectors would be enough to make good contact.

Has anyone been able to use this battery (352424) by maintaining the protection circuit board?

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Found this alternate battery as a possible fit :

LP332726

3.7V 150mAh

3.3mm x 26mm x 27mm

http://www.lipolbattery.com/lithium%20po...

I have not even opened my M400, let alone bought or tried this battery!

Does the M400 use the wired connector or does it have battery contacts?

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if I am not wrong > wired connector!

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Thanks Renato.

The only viable cell source I've found is AliExpress. I buy a lot of goods from various vendors there and most transactions have worked out well.

To find possible alternatives navigate to ' Home > All Categories > Consumer Electronics > Power Source > Batteries > Digital Batteries' and then search with the results for "lithium polymer 3.7v 190mah" or other mAh.

It seems a 352828 would fit and lipolbattery.com has that (240 mAh) but they want $60 ( cell $20 + shipping $40 ). Most alternatives via AliExpress are ~ $10, though I've not found a 190 mAh cell.

Polar charges a minimum of $25, plus tax and shipping.

Here's a 352525 160 mAh cell for $10

https://www.aliexpress.com/item/best-bat...

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Hi,

When you open the Polar M400 watch you will find four 000 (triple zero) size Phillips screws holding the electronics board. Removing those enables you to remove the electronics board. Doing so, you will find a separate USB connector for data exchange and charging. In my watch the USB connector stopped working and therefore the watch is dead. This happened after two years of use. I am now looking for a replacement. If someone tells me how to upload photos, I could offer photos of the opened unit.

-- AM

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Hi

I am experiencing the same issue with the USB connector and cannot find the piece to fix it on my own.

Thanks for helping,

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The problem does not come from the USB connector of the watch but from the cable. I have to change the cable very regularly. For some reason (acidity ?), the cables are damaged when they are used to charge the Polar M400!

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Beinstein will be eternally grateful.
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