Re-thinking equipped vans' electrical set up

Hi all,
My friend and I are studying an innovative solution for modernizing the electrical system in equipped vans. One key element of our solution would be to reuse salvaged electric bike batteries, and to reassemble them in a battery tailored for vanlifers needs.
Thanks to your experience, could you please help us better understand the needs and the use-cases of the electrical systems in equipped vans via this short survey ? (max 3 minutes to fill it in:)


We thank you in advance!

Jonathan and Timoté