Summary

Had a load of AA & AAA cells rolling about so made this on Freecad 0.21.2.
I normally work in Inventor but thought I'd persevere with Freecad which is ok for simple stuff like this.
Made to fit in some plastic boxes I have 62 X 97X 27 mm high without cells, 53 with cells.
Added the cross holes to help keep the base flat, first attempt curled off the bed mid print.

Print Settings

Printer Brand:

Creality

                                            <p class="detail-setting printer"><strong>Printer: </strong>                     <div><p>Ender-3 S1 Pro</p></div></p>                                                                                <p class="detail-setting rafts"><strong>Rafts: </strong>                     <div><p>No</p></div></p>                                                                                <p class="detail-setting supports"><strong>Supports: </strong>                     <div><p>No</p></div></p>                                                                                <p class="detail-setting resolution"><strong>Resolution: </strong>                     <div><p>0.2</p></div></p>                                                                                <p class="detail-setting infill"><strong>Infill: </strong>                     <div><p>20</p></div></p>                                                                                <p class="detail-setting filament_material"><strong>Filament Material: </strong>                     <div><p>PLA</p></div></p>

AAA & AA storage block