I don’t have a WiFi dongle, it’s connected via Ethernet to my network switch.
I recently had QCELLS solar/battery installed and i’m just starting to go down the HA route, would you be able to give me some time and help me get this setup on my home assistant server 
After years of successful request, today the REST integration started to fail because of a certificate mismatch: a request to https://qhome-ess-g3.q-cells.eu is returning a cert *.solaxcloud.com
Error fetching data: https://qhome-ess-g3.q-cells.eu/proxyApp/proxy/api/getRealtimeInfo.do?tokenId=<removed>&sn=<removed>failed with Cannot connect to host qhome-ess-g3.q-cells.eu:443 ssl:True [SSLCertVerificationError: (1, "[SSL: CERTIFICATE_VERIFY_FAILED] certificate verify failed: Hostname mismatch, certificate is not valid for 'qhome-ess-g3.q-cells.eu'. (_ssl.c:1032)")]
Is the https://qhome-ess-g3.q-cells.eu/proxyApp/proxy/api/getRealtimeInfo.do?tokenId=<removed>&sn=<removed> url still valid? Anyone experiencing issues with the integration?
Answering my own Q: switching to the SolaX Power - Home Assistant integration, using the local address of the dongle connected to the inverter, the serial number as password it works perfectly for a QCell inverter of type Q.VOLT_HYB-G3-1P.
Had the same thing happen indeed. Yesterday stopped receiving days from the API. Although i don’t get the certificate error, i get a ‘It works (https)’ result.
Still trying to figure out how to get the data as i haven’t yet figured out what the local ip address would be to see if it can work with the solax integration.
I’m having the same problem. Mine hasn’t been connecting for 5 days. It seems the server https://qhome-ess-g3.q-cells.eu/ is down. I’m trying to set up my HA as @republic1815 suggested, but besides having dozens of devices in my house, it’s already hard to identify the right IP. Is the port 80? Is the password the wireless device name in all caps?
I correct, I connected, using the solution of @republic1815 via SolaX Power.
Was only hard to fine the correct IP address, I’check one by one.
Port is 80, password wireless device name (all caps).
Great, i managed to connect it in HA as well now. I was wondering for a while what the Espressif device connected to my WiFi was…
Interesting to know that the wifi dongle is using an ESP32 chip 
The problem is: reconfiguring all sensors already used in HA… long job
Yes, seems so. With the website itself you are not able to get a login screen. Only the app on smartphone is working. So I think the main problem is the website itself…
Is the SolaX Power - Home Assistant integration a good alternative?
Considering I have it linked to an influx database with a Grafana interface, it is rather annoying for sure 
Another afternoon refactoring, sigh
After a couple of days I am resorting to running a container locally with the squishykid/solax: 
Solax Inverter API Wrapper library, which I suppose is used in the Solax integration, to get raw data from the inverter (dongle) into an excel file.
I noticed no consumption in the energy dashboard in HA for extended period of time, as shown here via the integration, and I am also getting the same flat (always same number for hours) reporting of On-grid total yield, On-grid daily yield, Total feed-in energy, Total consumption from the raw data, while power & voltage etc. are fine.
My current hypothesis is that QCell is messing up greatly: first the cloud API stopped working, now this Solax integration might not seem to be the solution as the inverter Q.VOLT_HYB-G3-1P is not returning good data.
For those who invested time into the QCell REST based integration, carefully tailored by @welcomeha to the benefit of all of us, the QCell server have been fixed: the certificates are now (2025-01-12 afternoon in Europe) compliant to the URI and the data is coming through!
The url qhome-ess-g3.q-cells.eu/proxyApp/proxy/api/getRealtimeInfo.do?tokenId=token&sn=123 is now returning data with the proper cert!
I have to add ‘inverterSN’ first line in jason_attributes.
True, now the QCell server is back. Has anyone seen the new web page displayed on the site https:qhome-ess-g3.q-cells.eu? It’s very nice. It would be nice to integrate it into the Home Assistant dashboard.