Ten thousand images have been successfully stored in a single section of a disk-shaped, iron-doped LiNbO3 crystal using spatio-angular multiplexing with a convergent spherical reference beam, resulting in an areal density of 33.7 bits/μm2. On this basis, the batch thermal fixing technique was applied to holographic disk storage. 5000 high-resolution images, divided in four batches, have been stored and fixed in the same crystal again but within a smaller area, resulting in a higher areal density of 50 bits/μm2. The application of convergent spherical reference beam and optimized optical set-up eliminated the detrimental scattering (from the crystal surface) and prevented it from entering the image detector. The images were reconstructed with good fidelity.