iPad will not respond, black screen, have tried force restart, etc.

Hello,

I haven't found a discussion question similar to mine so I thought I would give it a go.

I bought my iPad, model A1893, about two years ago. I used it occasionally, always kept it clean, dry, gentle use. A year after I bought it I brought it to Hawai'i and it was working great, I had it in my backpack in a car for a couple of hours. That night, it would not turn on. Black screen, no apple logo, no response to charging. I charged it for a long time, I tried the force restart where you hold the sleep and home button hundreds of times, every tip on the internet to try and get it to work again. I plugged it into my laptop, no response on iTunes. I eventually gave up, shelved it, and let it be.

A year later I'm still stumped. It was in great condition. So I took it to a Best Buy to see if they could troubleshoot the issue. They tried a different charger, they tried the same issues as I did, and eventually they offered to replace the iPad, they had no answer.

I guess I'm a little stubborn and I want to know more opinions. Does this sound like a battery issue? Should I replace the battery? I don't want to spend the money if it won't fix the problem. Or should I just give up and maybe get a new one someday? Let me know if you have any tips.

Thank you!!