The rechargeable battery I use lasts up to 14 1/2 hrs. That works fine most days but if I’m up early it means around 8:30 pm it will start beeping to let me know it’s ready for a recharge. I haven’t gotten in the habit of remembering to pack an extra battery in my bag when I go out at night. I’m so dependent on my implanted ear now that when the battery dies my hearing aided ear can’t recognize speech nearly as well as before. It’s really strange how your body adapts to these changes. Here’s a photo of my recharging kit. I numbered my batteries so I can keep an even rotation of charging. MedEl also gives you two other battery options, one with 3 disposable batteries and one with two. The 3 pack lasted me 4 days. The smaller 2 pk is nice if you are more conscious of the large size of the processor hanging on your ear.