Not obvious at all to me.

This sounded very definate to me and afaik is the last/latest official statement regarding 3rd party spares.

From a legal standpoint i think they dodged "consumer claims" regarding not providing spares albeit advertising user replacable battery by having sold a limited batch back in december...

Now that we have our community hack, i suspect them to keep silent on it. Which is a bit of a "go" in Jollas case. Only they can not advertise it from a legal (certification??) standpoint.

Remember how they handeld the "leaked" update (i don't remember the version number thou)?
Someone discovered that by testing through version numbers and doing a version --dup we where able to update to an unreleased version. They kept quiet about it when other companies would have barked like a dog to the users to not install it.
Heck, they even started the "early update" program shortly after leading to the suspicion they channeled the demand.

Ok, the comparison to spare battery is not fully doable, but i think it is a good sign that we did not have an official discouraging tweet like "Please do not use htc 310 spares, your phone may still explode"...

This battery on amazon isn't an original HTC battery but matches the Jolla specs...

http://www.amazon.co.uk/2100mAh-Batt.../dp/B00QR1J732

I suspect that was mostly to avoid any fallout from batteries that were being physically modified to fit and work - potentially a hazard with the battery technology in use.

The HTC battery, on the other hand, requires no changes in order to work.

But what I'm suggesting is for Jolla to just say: "Ok, we have made some tests and the polarcell HTC Desire 310 is now an 'approved' battery".

This is the part that's not obvious. This polarcell battery is already being sold in germany of all places. Not a shady bazaar on red district but in plain sight on Amazon. There's a shitload of certification for packaged LiIon batteries and I'm going to assume that Polarcell already complies with them all. It's not obvious which issues would Jolla have.

it seems, ebay just gives out vouchers, at at least i got one per email recently.
you get 10€, when you buy for at least for 20€, so i just ordered 2 polarcell batteries for about 25€.
that's a good deal, i guess

instead of paying 50€ for 1

Jolla could well profit from announcing having found a spare battery supplier. It would have cost nothing but an official blog post and some testing as you correctly say. The fact they did not already do (since two weeks) tells me that some legal issues keep them from doing an obvious step from user perspective.

Could it be that Jolla is obliged to provide warranty for the whole bought package (Phone, Battery, Charger) and its combined use?
Publicly announcing compatiblity with another battery may take them into trouble if those fail, regardless the perfect build quality of e.g. polarcell. Maybe if their original battery fails in a Jolla Phone ( and hurts someone), they have a special insurence from the ODM?

Just wild guesses, but some legal stuff is the obstacle for sure.

At least that golden desire 310 2450mAh battery sometimes refuses to charge if you reach 100% and then replug the charging cable ie. you need to reboot the device to get it charging again (which is quite a usability hit). And quite many desire 310 batteries are fakes or b-quality ripoffs. I haven't seen powercell one, so cannot comment if that one has similar problems or not (maybe it has better quality if your lucky).

Most likely Jolla as company will never endorse any other battery than the original one which has Jolla-label in it. Even if battery dimensions seems to match it still can have charging problems like above. And like always this is just my personal views and not representing any company.

It is perfect build quality as always from Polarcell!
Been using a polarcell in n900 since ages and now also no problem in Jolla since Monday!

Yay!

See what just dropped in my mailbox