Very convenient and compact multipurpose Power Ban

18 July 2023

I don’t normally write product reviews, but in this case, I think it matters more than usual. When I purchased the Telesin Power Bank in July 2023, it was close to (if not actually) one-of-a-kind: a Power Bank with USB slots that *also* has integrated slots for GoPro batteries. However, 7 months after the product was released to the public, there were few reviews available and significant unverified aspects about its operation remaining, with several customers on other sites claiming their item was faulty. Nevertheless, I suspected this was a vocal minority and took a calculated risk to purchase the product. I am here to describe my experience with it. TL;DR – it has slight quirks, but it works well. I have used this item almost daily for over three weeks. I found it very convenient to carry it around in my GoPro carry case along with three batteries. A GoPro running continuously will drain its battery faster than the power bank charges a single battery, so with a minimum of three GoPro batteries in rotation (one in the camera, two in the powerbank), you can continuously swap a totally drained battery with a >95% charged one. Starting the day with a full powerbank and three full batteries gave me ~12-14 hours of continuous filming at 1080p/24 FPS without any trouble. It has completely replaced my need for the official GoPro dual battery charger. Overall, I am pleased with this purchase. At this moment it appears to be a unique product which does a reasonable job at filling a specific use case for people who want to charge GoPro batteries in a very compact fashion, instead of having to carry around three separate items (a GoPro battery charger, a regular USB powerbank and a USB cable between the two). To be honest, I’m surprised there aren’t more products like this from other manufacturers. There could still be improvements to this product, but I think it merits 4/5 stars. Here are several additional observations: - Both of my GoPro charging ports work *with the plastic latch closed*. This sounds like it should be obvious functionality, but there are multiple reviews out there with people saying their units did not charge GoPro batteries properly, or only charged them when the plastic latch was open. At the very least for me it operates as expected. I only have Hero 9/10/11 model batteries (I did not test the supplied insert for Hero 5/6/7/8 batteries), both the standard version and the Enduro version. Both versions charged properly in a timeframe consistent with the manufacturer’s claims (~150 min for a full charge). Interestingly, several times the batteries charged to 100% (as judged by putting them into a GoPro Hero 10 and looking at the reported charge), but the red LED light never turned green. Sometimes the green LED turns on at 100%, but generally not, so don’t trust the LED colours. I’ve seen similar confusion happen to the LED lights on GoPro’s official dual battery charger, and I don’t know why it happens. Ultimately, if the GoPro Hero reports 100% charge, then it’s charged and that’s what matters. I will say, however, that the charging slots on my item have slightly different sizes – both function correctly, but one of them is a considerably tighter fit for the battery and requires somewhat more pressure to insert, as well as being tougher to pull back out. It’s not an issue with the GoPro battery sizes being slightly different, because the same charging slot is tight when the batteries are swapped around. This could be a minor fabrication defect in the plastic casing, or maybe just slightly loose tolerances with the plastic case mould. - I charged a Samsung mobile phone using the USB-C to USB-C cable provided along with the powerbank, and it worked just fine. The powerbank was indeed capable of fast-charging, as confirmed both by the mobile phone display itself and the fact that it charged at a similar speed as to when directly connected to a wall socket using the proprietary Samsung charger included with the phone. - The powerbank charged with no issues when connected to a wall socket using the aforementioned proprietary Samsung phone charger, and obtained a full charge in somewhere around 3 h (the manufacturer claims 2.5 h with 20 W fast-charging). - The powerbank indeed was capable of pass-through charging (simultaneous charging and discharging), in accordance with the manufacturer’s claims. In one test, I was able to charge the powerbank by connecting it to a charging laptop via the powerbank USB-C to laptop USB-A ports, with the powerbank simultaneously charging two GoPro batteries and an iPad connected to the powerbank USB-A port. It took around 16 h to get everything to 100% charge, because the laptop could not fast-charge the powerbank, and there were three other devices draining the powerbank simultaneously. One thing I noticed is that if the powerbank is fully depleted and has GoPro batteries inside that are not fully charged, then just charging the powerbank over

(4)