For others' information, Brogen has replied as follows:
Hi David,
. If your dashcam pulls more than 2.1 amps, you may still run the Venture dead simply because your outputting more power than inputting. However, I doubt this will be the case. Once the car is off, the venture should be at 100% and run you dash cam until it is dead.
Let me know if you have any more questions.
Best,
Brogen Reed
Interestingly, but not surprisingly, this fellow never directly answers your questions, especially in regard to safety. Instead he says,
"The venture 30 will indeed be charging while using it to power the dash cam." The fact that it will
accept a charge while discharging doesn't answer whether it actually has the appropriate circuitry to properly do "pass-through-charging", a term I notice you avoid using when you send these queries to these companies.
The simple fact is that even if a power bank can do pass-through-charging, they were never designed to be permanently connected to a power source and left inside an automobile where they are subjected to constant shock, vibration and temperature extremes. Pass-through charging is designed to be used periodically, not full time.
This whole "pass-through-charging" mentality here seems to be a strange metaphor of a power bank as a kind of bucket full of water leaking through a little hole in the bottom where the bucket is constantly being being refilled from the top to replenish it.
But that is not how lithium-ion batteries function. They rely on a very energy dense, potentially volatile electro-chemical reaction involving the migration of ions between an anode and a cathode in a processing that is specifically intended to cycle. Unlike a bucket of water, lithium batteries are susceptible to stresses that cause them to deteriorate.
At this point, since you have been asking the same basic question in this thread for 15 months now it is clear that you are going to keep asking this question until
someone gives you the answer you want to hear, so hopefully the worse that will happen is that you end up with a prematurely dead battery pack and nothing more.
"What is Pass Through Charging" (Charger Harbor)
https://www.chargerharbor.com/what-is-pass-through-charging/
Some quotes from the above article:
"In the short-term, Pass-Through charging can be very convenient but in the long-term, it can harm a power bank’s capacity quite a lot."
"Ultimately, we think that Pass-Through charging is double edged. It’s a great way to keep all your devices charged in the SHORT-TERM. In the LONG-TERM, however, the power bank will be damaged quite a lot. We may recommend getting a high capacity power bank for Pass Through charging, but we HIGHLY recommend to not use Pass-Through charging too much or not at all."
