There are many posts in this community on alarm panel integration. Search for your brand of panel to see results. Konnected is also another option too.
At my previous house, which had a wired alarm system, I used the ecolink sensors that allow you to connect and external contact. I never used the ADT system , but I attached one of the sensors in the link below to each zone I wanted to monitor, and they worked well for me.
I use the envisalink v4 with my Honeywell vista 128 panel and use this Vista App which also requires node server. [RELEASE] Honeywell / Ademco Vista 20P Integration
Your window sensors are more then likely in series in one to three zones, so you will only be able to monitor the zones. I did replacement windows which destroyed my hardwiring so I ended up with Honeywell wireless battery powered sensors which gives me integration per window.
Then I use WebCore to control my Thermostats, turning off AC/heat when windows are open, and more…
Yeah I missed the no battery solution part, so yes these are battery powered.
I don’t see why they couldn’t be tied in parallel with your security system zone. I used this in place of the security system. I guess the only advantage would be less batteries to change, as you would only need one per zone as opposed to one per door or window.
I attached the contact switches with batteries (mentioned above) to my my existing alarm system’s door and window contact in the control box, 4 years ago. My batteries are at 80% still. You may have to change out the battery once a decade. Using battery operated sensors are not a hassle at all.