Polar H7 heart rate monitors are awesome. They run on bluetooth low energy, which for me is great because the fewer devices tracking my workout, the better! However, if you find it’s time to change the battery (you experience erratic heart rate data or drop outs or no data at all), here are your step-by-step instructions. Users rejoice–your inner handy-person awaits!
Directions to change battery:
1. Using a coin, open the battery cover by turning it counterclockwise to OPEN. Remove the cap.
2. Using a sharp edge (knife), lift the battery out from inside the cap. See Photo 2.
3. Insert the battery (CR 2025) inside the cover with the positive 
side against the cover. Note: the positive side is also the side with the writing; insert the battery with writing side down. Make sure the sealing ring is in the groove to ensure water resistance. See Photo 1.
4. Place the cover back into the connector. Be sure to do this carefully by lining the arrow on the outside of the lid directly with the dot on the connector next to OPEN.
5. Use the coin to turn the cover clockwise to CLOSE.
Note: When changing the battery, make sure the sealing ring is not damaged, in which case you should replace it with a new one. You can purchase the sealing ring/battery kits at well-equipped Polar retailers and authorized Polar Services.
For more information about using the Polar H7, read the manual.
Good and usefull article to replace battery for polar hr 7 ble
It is tricky removing the battery but make it easy by using a bit of tape instead.
How do you know if the chest strap battery is low or the watch battery?
How do you know if the chest strap battery is low or the watch battery?
I agree. It's a real pain in the tookus to realize the battery died at the start of a run. Grr
I have terrible luck removing the cover. What is the magic coin to use? Everything I have tried did not grip the slot and ending up damaging the slot. I've tried quarters, and nickels but all seem too small.
@Mike: I happened to have some change left over from a business trip. I think that the magic coin is a 2 Euro coin. I had already stripped my cover so I need to replace it as well. Haven't found a source to buy one though.
I had stripped the first cover and sent it to polar, they decided I also need a new chest strap for about $65.00. Now I need to change the battery and the thing won't turn with quarter or half dollar. Maybe go to hardware store and try the washer selection.
A push pin (or bulletin board pin) works much better than a knife to remove the battery. The knife I tried seemed to risk damaging the plastic casing around the battery and was hard to get under the battery. The pin popped it right out. As for the coin to remove the cover (the prior step before removing the battery) a dime worked perfectly. Mine is a new monitor (January 2015, Polar low power bluetooth), and I see some of the older ones may be different.
An AA medallion works great ; )-
Hi, I use Endomondo app on my Microsoft Lumia 1020 phone and the battery level is under Setting -> HR belt.
Mike Base YEs 2 EUR coin is the best to open it.
Hi there…what's the actual size of the battery please?
I used a magnet to get battery out
I used a penny
While reading the manual… it's on the polar beat app
CR2025 (3V)
the battery cover has the notch stripped and I have not been able to find a way to open it. Any sugestions?
Hi – no, sorry. Bummer! Maybe someone else can help but I’d probably call polar, see if they can replace something or… ?
My heart rate won't open with a coin. Almost like it is stuck. Any suggestions
Hi Kimberly – bummer. I’m not sure. It may be too much salt from sweat has it stuck. I read this a while ago (http://www.instructables.com/id/Save-your-Gameboy-Color-and-other-small-electronic/) and with that, think maybe a swab qtip with vinegar around it a couple times might help loosen it up? Of course, try it only if you are comfortatble and at your own risk, probably shouldn’t say anything because I really don’t know, sorry.
You can actually use your new battery to open the case as well… it fits better than most coins!
Can you use a cr 2032 instead of a 2025 as well?
Sorry I don’t believe you can. Some brands of HRMs use one, some the other, but I don’t believe they are interchangeable.