I just had my first ever LiPo accident!
And I have been using LiPo's since 2002-2003 in fixed wing flight and boats.

Ordered some Auline 1s 300mah LiHv with the connector on the end of the cell, and while picking the battery up from the box it flashed from the connector and smoke started spew from a needelpoint size hole in one corner.
Those 1S LiHv batts are dangerous!

Right now its out in the middle of the lawn, leaving it there until tomorrow before picking up the debris.

I have had LiPo's bent and smashed in crashes or swollen from drawing way to many C's from them but never had a smoke and/or fire related accident before.

In the future I'm treating those 1S LiHv's as live bombs and probably focus more on 2-6S quads.

Always treat LiPo with respect regardless of the size. Glad nothing worse happened to you.

I always treat LiPo's with respect, and this was certainly not a case of not treating LiPo's correct, I took a brand new cell from the box and it flashed from the connector and started to spew smoke within a second.

I opened a box with four brand new 1S LiHv's, I had already put the first two I took from the box on charging, this was the third one I took from that box and the first time i touched it, really lucky this one did not make it to the charger!

Wow, were they new in the box and it discharged like that as you were unpacking them?!
If so, that's pretty unacceptable.

Yes, they where new in box, I was unpacking them to charge them for the first time when this happened, and this cell flashed from where the plastic casing around the connector mets the cell as soon as I took it out of the box!

Not acceptable! Must have been a short in the connector or faulty soldering from the connector..

more cells = more possible risk for failure.

we commonly charge 1s packs with more c than other pack, at least in my area, but there arent more issues about quality. gnb packs can be bought as 1s, or same cells in 2s/3s/4s...configuration - dont metion the number of cells, its about quality

maybe you shouldnt choose auline again - but asking for a statement or cashback, undagerousreplacement... would be my route, checking their responsibility
i use 1s packs made by tattu and gnb, hadnt any issue so far - give them a try
i like to try some dogcom 1s lipos in future

I agree that they owe you compensation and I hope for everyone's sake that they take this as an opportunity to tighten their quality control, but I'm tempted to shy away from Auline batts after this report.
Glad all ended safely on your end.

I've sent a mail to my local FPV shop where I picked them up. The only reason I did go for the Auline's is that was the only ones in stock fitting my Mob6.

On my 2S+ quads I mostly use Tattu or GNB, and not a single issue yet.

Maybe its just me, but LiHV's seem more reluctant to problems, the packs I got with the Mob6 did start to loose capacity and swell up after very few cycles, though always charged at 1C with a high quality charger and storage charged right away after flight, like I always do with my LiPo's.

This isn't the first issue we've seen with Auline LiPos. Check out CycloneFPV's YouTube channel for more info.

One saving grace is that at least this didn't go up in smoke in the cargo hold of a plane while being transported across the globe from China. It's one of the reasons why it's now become extremely difficult to purchase / import LiPos from abroad within some countries.

I only run GNB, Dogcom or CNHL (but do have some BetaFPV 1S packs as well) in 1S. So far I haven't had any great problems, but i'm anally retentive about how I handle them and charge them. Basically they go in an ammo box or metal container when charging. For the bigger stuff I charge using a SkyRC e3 balance charger and have never had any issue. Haven't had any puff yet, but one of the 2S 380's I bought last year got a bit weird over the summer, not holding charge any more, so i tossed it. I generally have many spare cells on hand, so if anything weird occurs I throw them and get a new one.

I have never had an Auline, but from what you said i'd avoid them in the future. The Dogcom packs are nice if you need BT2.0 and the CNHL packs are nice if you need PH2.0. I would suspect the Tattu packs would be the same, but I've never seen a 1S Tattu pack, at least they don't sell them over here AFAIK.

If you don't have a fire extinguisher, get one, ideally a CO2 one and do all your charging out of your house or very near a door, in an ammo box (minus the ammo).

I mostly use Tattu or GNB because that's what I can buy localy.
If I could have bought some 1S of another brand than Auline I would have, but they were the only 1S LiHV's in stock, and they have the PH2.0 connector as do my Mob6.

I really dont like when the connector is attached straight to the cell, I prefer leads from cell to connector.
I have had the connector failing on the ones with "built in" connector on several "micro" fixed wing 1S LiPo'

Maybe I should sacrifice some power and try some 300~450mah 4.20V LiPo instead of 4.35V LiHV on the micro toothpick I'm going to build with the AIO, 19k kv motors and cam from my Mob6?

I have two fire-extinguishers, a fire-blanket and a multi gas/low oxygen alarm in my flat since I have a gas stove and charges LiPo's here.

I always charge LiPo's in a steel amo box and never leaves the room while charging

No fire extinguisher or fire blanket will put out a LiPo fire which is a self-sustaining thermal runaway chemical fire. This is why firefighters find it so difficult to put out fires on an Electric Vehicle if the batteries in it go up in flames (EDIT: there's an interesting video about that HERE).

A steel box will contain a LiPo fire until it burns itself out, or you can dump sand on the LiPo to contain the flames, but you will still get a load of smoke until the chemicals are all burned. The bigger the LiPo the longer it takes to burn itself out.

I did go out and check on it and it was cold and empty of energy.

You can't se the small hole where the smoke spewed out, but you can se that it's burnt and discolored in one corner where the hole where/is. 
The cell is swollen and the folded sides of the cell have unfolded, but apart from that everything except the burnt corner looks normal.

I don't feel like it's a good idea to treat it like unharmful since the chemicals inside, but I guess that the fault lies inside the plastic connector cover since it flashed from inside the connector right before starting to spew smoke.

I did get a mail from the store where I bought the LiHV's. They have sent me a new pack of 1s 300mah Auline cells and a 5-pack of 1s 300mah LiHV's of some other brand.

I'm going to check so those Auline's is in good working order really carefully when they arrive, I don't want another smoke incident.

I don't know what brand the 5-pack of cells are of, they just wrote "and a 5-pack of 1s 300mah LiHV's with approximately the same size and weight from another manufacturer", guess I'l see that when they arrive in a day or two.