# How long will my x 2 23a 12v battery last running a 300mah camera?

I’ve brought some WiFi cameras to run in bird boxes but the battery life on them aren’t very good at all. I’ve tried running them from battery power banks but they switch off after the cameras have reached full charge. So I’ve now order some a23 12volt batteries, will run x 2 side by side with a step down regulator to 5 volts 300mah. My question is how long would they last? A bit more info of the camera, it has a 300mAh battery installed, says in the instructions that it’s DC 5v and has a working time of roughly 100 minutes. I understand the batteries I’ve ordered are the GP Super 23a 12v which from wiki stats 55mAh each which I’ll run in parallel. I’m not electrically aware so hope I’m on the right track.. Thank you!

• What is the capacity of the batteries? Commented Feb 19, 2020 at 14:16
• Your question is unanswerable without detailed information about the power consumption of the WiFi cameras. Also "a23 12volt batteries" means little, do you mean 23 Ah? Commented Feb 19, 2020 at 14:17
• Sorry the batteries I’ve ordered are the GP Super 23A 12v which I’ll run in parallel. I’m guessing they’re 23amp per battery or I could be misreading understanding what the packaging says.. Commented Feb 19, 2020 at 15:00
• The WiFi camera has a 300mah battery already installed, which has a run time of roughly 100 minutes. Says in the manual voltage DC 5v Commented Feb 19, 2020 at 15:15

Assuming two A23 batteries in parallel at $$\12 V\$$, the charge available is about $$\110mAh\$$ ( $$\55 mAh\$$ each). So, converting the $$\12 V\$$ to $$\5 V\$$ with average efficiency, the capacity will be equivalent to $$\220 mAh\$$ at $$\5 V\$$. So, it would last about 220/330 hours or about 40 minutes.