rtc and battery
 

I have waveshare rtc seems the battery is locked in, not removable.

I looked into different rtc unit, that sounds nice on amazon, it needs slight mod to use non rechargeable battery, removing tiny resistor.

I was wondering if the waveshare rtc battery can't be removed does that mean it might be rechargeable?

https://botland.store/rtc-modules/44...422371777.html
based on this it is a replaceable battery.

the rectangle tab in the attached is attached to the battery, like this on both sides, you can see two little indenations in the red highlighted area, how do you get this apart?

this was a little helpful

I don't want to break soldered connectors to battery.

I don't really know, but you can easily find another one: https://www.dfrobot.com/product-879.html

In my experience, RTCs with non-rechargeable batteries that aren't designed to be replaced are only good until the battery dies. Looking for an alternative with a replacable battery is prudent. I'd advise a DS3231 for general use on the I2C interface, or a DS3234 if you're running via the SPI interface. I run both of these RTCs and cannot recommend them highly enough.

Thanks Exaga, I emailed waveshare about their card, response I got was "not rechargeable, it's soldered, sorry".

When I was looking into RTC, couple I found had to be modified to allow for not rechargeable, I'll follow up on what you recommend.

The most reliable and accurate RTC I have experienced is the DS3231 based ChronoDot. Not to be confused with the "ChronoDor" which is a much cheaper clone. The ChronoDot requires a CR1632 battery which will last for approx. 8 years before it needs to be replaced. The ChronoDot may be a little expensive but its quality is second to none.

There are many DS3231 based RTCs and (although I've tried and tested many different RTCs and controllers over the years) I tend to stick with this one. They're easy to install and configure/manage using the GPIO I2C interface, especially on the RPi devices. The rule of thumb with these RTCs is the size of battery it can accommodate - the larger the battery the less frequently it needs to be replaced. A DS3231 based RTC with a CR2032 battery is good for +10 years. The AT24C32 IIC model is a prime example - these are the ones I use and like most.

Hope this helps.