Hearing Aid Battery Holder - Keychain

thingiverse

Update 5/28/19: As requested by calania, an additional 1mm diameter has been added to the bottom part of the design to prevent common breakage at the thread location. This adjustment also required removing an extra 1mm from the top threading to accommodate the larger bottom diameter. The latest files for printing are the HearingAidBatteryHolderTop/Bottom - 1mm Diameter Added.stl, which were test printed at .1 resolution with support everywhere and came out perfectly. I'm always on the lookout for inspiration for my projects, and this one was provided by my dad. He recently received a diagnosis of tinnitus and got prescribed a set of hearing aids, which has greatly improved his mood and enabled him to hear things he thought were lost forever. However, he expressed frustration with frequently replacing batteries and how they often seem to run out at the worst possible times. A month ago, he asked me to design something that would allow him to carry spare batteries with him when he's out and about. He provided me with a few size 312 Zinc-air batteries to get the correct dimensions. I spent several nights brainstorming a design in my head that would be safe, compact, and easy to access. Last night, I came up with this concept and sketched it out in Fusion 360. I was thrilled to see my first prototype print fit together seamlessly. Only minor cosmetic adjustments were needed to get the design just right. I decided to align the torus-shaped keyring cutout with the position of the battery tray and added a raised arrow to make it easy to identify the top of the tray, ensuring that batteries wouldn't accidentally spill out when opening. I also used supports between the tray dividers, which helps them print straighter and adds a bit more material to keep the batteries snug but still easily accessible. I'm really proud of this design and was impressed with the results. I hope you guys will enjoy it too!