Just had my first experience jump-starting my 2012 Prius... I knew enough to use the charging points under the hood. Trouble is, the positive lug under the hood is tiny and buried in the fuse box! I had to try three friends' jumper cables before I found one that could squeeze in there. A search here turned up not much... what am I missing?
I took off the vinyl ends of a small spring clamp and clipped it to the jump terminal in the fuse box. Then I clamped my jumper cable large clamp to the spring clamp. For reference: 4 Piece Mini Small Spring Loaded Squeeze Clamp Set | eBay Posted via the PriusChat mobile app. You can also use a pair of vise grip pliers, you get the idea...
You're missing that the Prius shouldn't really ever need a jump since it doesn't crank. And when it does, the Japanese design has not been touched like it on the other Toyota Lines. The USDM Prius and the JDM Prius are very similar. The Japanese have small batteries and small terminals as standard. Your average set of jumper cables there is marketed as "motorcycle jump cables" or "compact jump cables" here. So carry some compact jump cables and be good with it. But keep in mind a reverse polarity jump in a Prius can be a $4k mistake. Investing in smart cables for $20 seems like the better idea.
You really don't need to use the elephantine monsters normally associated with the heavy currents (100+ Amperes) of conventional "jump starts". Bear in mind you're NOT turning the ICE, so lightweight gauge cable will be quite adequate, not much current is needed to boot-up a Prius's computers. I even read a post hereabouts where someone used 8 "D" cells wired together to jump their Prius!
You could also jumpstart directly at the battery, if you've got big clamps. Again, be very careful to avoid mixing up positive and negative, and get the underlying problem addressed ASAP: this is not something you should be doing on a regular basis.