Which Yihi mods do you have?
Mods with the SX130 30W chipset.
But those aren't the only ones that have been reported with this issue. If you search here and google you'll find laments/reports of other Yihi chipsets that have a high rate of quiescent current drain (most call it parasitic drain so that would be a better search term, but it's actually quiescent drain that I'm talking about here).
I've vented a battery 2 times in these mods by keeping the batt in the mod unused and on off (standby) for about a week or so. The first time it happened I didn't know what happened, I just went to use it and it was dead and found out I had a 0v battery. The second time I actually heard it vent and when I figured out what it was, again a 0v battery in the mod.
I understand that you should take the battery out of any mod that's not in use, I learned that the hard way

. However, I've tested just about every mod I've had in rotation so far and the quiescent drain is so little that it doesn't drain the battery hardly at all within a week. I'm talking less than 0.1v. And all my mods are cheap, mainstream chinese mods.
Only way to test this on a mod (easily anyhow) is to record the voltage of a battery, put it in the mod, turn the mod off and set it aside for a few days then test the batteries voltage. Then do it for a few more days if needed. Would never go a full week at a time since you have no idea what it's quiescent current is. Could be a bad idea. So test every couple of days instead.
I don't know anything about the YiHi SX130H-V2 but I wouldn't be surprised if it drains the battery more than any of your other mods after a week or 2 unused and in standby ("off"). It's a known issue, but I don't know if it's a known issue for all Yihi Chipsets. Yihi doesn't seem to GAS

, it's been known/reported for years now.
Edited to add: So to get back to my original statement, if these mods I have had an on/off switch (and I remembered to use it) that would negate the high quiescent current drain on these mods. I simply don't trust them even sitting overnight anymore. Although I do like using them. If I didn't, they would be in landfill today.