Capacitor across Vlo and Vhi on DAQ, switching power supply
Yes some low pass filter is common and essential. 

Technically it's called a transient suppression filter for : Conducted load transients V=LdI/dt, radiated crosstalk and anti-alias suppression (where the rise time interferes  with an error of the sampled value) . 

The details of the filter need to be defined in terms of your needs for timing and accurate voltage measurement or SNR.  i.e. if you are looking for a slow error recovery like low battery , fly home or slow down immediately, that affects how much you can filter the input with a low ESR cap for special low pass filter.

The most common method for measuring DC voltage accurately in the presence of a high transient spike noise is to choose the BW of noise to be suppressed and design a filter to suppress that to an acceptable SNR or the signal.

Since you have some sampling rate for data, your signal BW is likely to be DC to 1/3 of the sampling rate.  You must have some anti-aliasing filter to prevent additional errors from noise spectrum above the sampling BW appearing falsely as a signal.

This is not a complete answer and depends on your specs for SNR, BW , load spike noise levels and signal integrity or acceptable error.