Sony A7ii/A7Rii Battery Grip/Extender

thingiverse

This is a Sony A7ii and A7Rii grip with integrated 18650 cells. It may suit other Sony A7 series, however I do not have any other models to verify if this will fit. It is designed to fit the commonly available battery eliminator found on Ali Express as shown in the photos. 2023-09-03: Added another battery insert model for another type commonly available on AliExpress. ==Required== * 4x M3x5 * 1x M3x15 * 9x M3x25 * 1x Sony Battery Eliminator (as seen in pictures, commonly available on AliExpress for cheap) * 4x Li-Ion 18650 cells (can be recycled from old laptop batteries) * 1x Mini toggle switch (Optional, this just a battery disconnect to extend life when in storage) - https://www.jaycar.com.au/spdt-sub-miniature-toggle-switch-solder-tag/p/ST0300 * 1x DC barrel jack for charging - https://www.jaycar.com.au/2-1mm-bulkhead-male-dc-power-connector/p/PS0522 * 1x DC barrel jack for output (optional if you wish to power external devices from the grip directly) * 1x 2S Li-Ion 18650 BMS - Shown in picture, commonly available on eBay/AliExpress. * 1x 8.4-9V DC power supply for charging == Printing == All four parts are designed to be printed without supports. The battery insert is designed to be printed with it's flat back on the print bed. Because the sections are designed to be screwed together it is important that they be flat, it is suggested to print using a brim for all parts except the battery insert. Printed using a 0.4mm nozzle in PLA on an Ender2. == Wiring == This houses four 18650 Li-Ion cells wired in a 2S 2P configuration, that is, two sets of cells wired in series, then in parallel (see image) which is then connected to the BMS. If you are not familiar with basic electronics please do not attempt this project as I will not be providing detailed instructions on how to build this battery/grip.