Cygnett Boost 10K V4 Power Bank (Black)

battery swelled after off and on use of a year, most left in a cool dry draw and only used occasionally, noticeable swelling after not long, expensive and bad quality do not buy this crappy thing. Was forced to throw out due to safety concerns.

don't buy this product! we found this powerbank expanded on our drawer after not using for months. concerned about the safety of this product.

Absolute junk. Worst power bank I’ve ever owned. Takes 17 business days to charge. Only charged my phone to 50% then completely kicked the bucket and now won’t charge. Tried switching cables, wall sockets/adapters. You name it I’ve tried it. Purchased for an oversea’s trip and didn’t survive the first night. About as useful as a fly screen on a submarine. 👍

It stopped working after 2 weeks, but did work well for those 2 weeks

This powerbank is a joke!Bought it on August 2025 and for the past weeks it started to be funny.You charged the pb itself for 8 hours for 100% charge then it charges your iphone 45% for 2 hours.Wow!Not worth the money and effort.I suggest you dont buy!

Pretty worthless. It would only charge every now and then, and now, after < 10 recharges, it wont charge again, no matter which cord, no matter which block or charging device. I'll be returning it ASAP.

Just doesn’t work anymore. Won’t charge the battery

Worst Power Bank I've ever used. Definitely not even worth 50 bucks. Charges your devices at a slow pace..Uses almost half the battery to charge an iPhone to 95%. When its time to charge the battery, forget about it.. Seriously.

I have three of these. One of them stopped working, one had the battery expand and broke the case ( I’m not game to use this anymore. And one is still working great.

Worked perfectly until it accidentally slipped off my desk. Now the thing doesn't even hold charge. Disappointing.

Had it 2 days and it's already expanding. I do not recommend this product.

Good to use on holiday to keep things changed up..

Very sturdy. Very long battery life, I can use it for 3 days traveling without recharging. Proud of Aussie brand!

Very happy with this power pack. It is easy to use, efficient and charging and doing everything I expected.

This beefy brick of a powerbank is honestly incredible for when you're taking long trips like flights. During a multiple day trip to and from Melbourne I only had to charge it onces and it recharged my phone multiple times over. The only issue I have is just how HEAVY it is, it really does feel like a brick in your hands, but in general, pretty perfect

Not 10,000mAh, but at least it's cheap and reasonably well made. After charging the battery bank up overnight I tested this unit powering a gopro camera over almost 10 hours; with between 0.7 and 0.9A load it delivered 6,888mAh before reporting 0% and cutting out. This is par for the course for most cheaper battery banks - they never meet their rated specs. The USB-C output is only 5V but again as expected at this price point. The battery bank appears to be well made and the loop in the case is a useful feature.

Was going overseas and was in a rush to buy a powerbank to charge me and my wifes phones and ipad and our earphones, was able to charge upto 3 devices which at times we needed to and when everything was fully charged there was still a lot of charger left. The Cygnett Boost 10k V4 is seriously a big bang for your buck. Fully recommend this for those on a budget and going overseas. This does the job

I bought the 20k originally and that was so heavy and d very slow with charging it (also has a dodgy cord) so sent to the 10k. Much lighter and the cord is good but these banks take way too long to charge up to use again... I'm talking all night

Product is already expanding/bulging after only 1week of being used.

Very powerful, fast charging and long lasting in battery life only con is, it takes a while to charge up.