Help: Phone randomly restarts & sometimes stucks in boot loop! - Honor 9 Questions & Answers

Hey there,
as mentioned in the title my long used Honor 9 started to randomly restart (sometimes multiple times). I can be triggered when opening/closing different apps, browsing through youtube or listening to spotify. Sometimes the phone even restarts after I entered my sim-pin, so I can't use it at all at the moment which is very frustrating. Most of the time, if the phone restarts, it ends up in the eRevovery Mode or the Emergency Backup Mode. There I only have the option to shutdown/restart/backup/reset the phone. I always press restart and with a bit of luck it starts completly normal so I can use it... until it restarts again on its own at some point...
I never had issues with this phone until last week. The last few days those random restarts and boot loops ending in the eRevovery Mode happened very frequently.
Here is some info:
I use this phone since November 2017 with an external 128GB SD-Card
4GB Ram, 64GB internal memory
SD-Card used 100GB/128GB, Internal used 30GB/64GB (so technically there is enough space left)
EMUI 9.1.0.231 (strangely it shows the same version as an "update" sometimes, see picure down below)
In 2019/20 I changed the battery once (old battery was bloated/swallen, no problems occured after the replacement)
My phone is not rooted
... if someone need more informations about my phone: just ask!
What I have already tried to fix the problem:
Downloading "the same version update as already installed" (see picture down below)
Deleting unused apps
SD-Card removed
Cleared System Cache
Using "safe mode"
Doing a factory reset
Unfortenately nothing helped.. Someone has an idea whats the problem and how I can fix it?
Thanks in advance!
Attached Picture: Phone Version
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UPDATE:
I think I found the issue. I just saw the reviews of the battery I changed in late 2019 (see: here). Nearly every review is stating that this battery is causing the restart problems. This is a little bit strange because I used this battery for like 2 1/2 years and had no problems until early 2022 when I suddenly experienced the same issues.

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Has a new battery solved the issue?
I'm currently having the same issue.