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Jolla battery data sheet (includes a poll)

asked 2015-07-29 20:12:41 +0300

simo gravatar image

updated 2015-08-14 00:12:38 +0300

There has been a lot of discussion on availability of spare batteries, and urgent need of those has even taken us to test with other manufacturers batteries, risking even the user safety according to warnings posted by Jolla. However, the situation hasn't improved, different batteries seems to still be tested (somewhat understandable), so let's have a Sailor answer to this:

What are the official specs of Jolla battery, including all the needed information to manufacture one similar one?

If we could have this data on openness, community might be able to find a smaller manufacturer to provide us these long wanted spare batteries. If not officially supported, ok, if voiding the warranty, ok, but at least safer and right sized batteries could be found at some point this way.

I'll accept an answer with the required data, but I'm happy to close this question as outdated if I see another post sharing that official batteries are available. Thank you in advance Jolla, I'm sure you want to help us on this!

EDIT: Simple comment-poll added as an answer, direct link

EDIT2: Results after two weeks: 138 answers, 84% willing to buy a spare battery. Poll is open for new votes

  • 22 I don't think I will need a spare battery within the next 3 months
  • 8 I'd buy a spare battery from Jolla Shop (only) for 25€ within the next 3 months
  • 89 I'd buy a spare battery from Jolla or 3rd party for 25€ within the next 3 months
  • 10 I need one even faster, and I'm prepared to pay even a bit more
  • 9 I need one, but the price should be less than 25€ for me to buy
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I'll hijack it a bit but can you also make a poll/questionnaire of how many people have actually had problems with their battery and actually need a spare.

It seems to me like one of those "i have to have it because i can" things and not an actual problem. If it was not user replaceable i doubt there would have been so much fuss about it.

ApB ( 2015-07-29 20:28:26 +0300 )edit

I DO! Six hours a day of battery is an insult to my intelligence. I run the whole day long with an extra battery pack attached. And the microusb connector enjoys the constant in and out.......

lupastro ( 2015-07-29 20:33:30 +0300 )edit

@ApB I actually had a poll on this in April on JPF, resulting 48% of ppl who answered there were prepared to buy one. A poll for wider audience is possible too, but here's that small one:


simo ( 2015-07-29 20:40:27 +0300 )edit

would be nice. even nicer would be an official possible replacement however i think the correct size, voltage, max voltage, capacity is all you need and that is stated on the original battery

pawel ( 2015-07-29 20:43:27 +0300 )edit

@lupastro Is this a result of your use case or problematic battery?

@simo Ready to buy one doesn't mean that they have problems with it. Oh I can't see the pole i don't use FB but that doesn't matter :P .

ApB ( 2015-07-29 20:47:45 +0300 )edit

8 Answers

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answered 2015-07-30 21:43:40 +0300

objectifnul gravatar image

updated 2015-08-02 20:11:09 +0300

No real answer for me, as I was lucky enough to get a spare battery last year when a limited sale was offered by Jolla. If I wouldn't be lucky, of course I'd purchase a spare battery for 25€. I always take care of my stuff: for me the usual lifetime of a smartphone is at least four years, using two batteries and two leather cases.

Having designed a phone with a removable battery, then using this feature as a marketing argument, then not selling spare batteries, is a major fail IMHO. Some cheaper phones come with two batteries...

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answered 2015-07-31 15:20:12 +0300

Giacomo Di Giacomo gravatar image

This is not official from Jolla, but it is confirmed that the Jolla battery is the same as the one used in the HTC Desire 310. User @Robomike just tested one and it works. This is great news since it puts an end to the battery issue.

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Great news, indeed. Thanks!

lakutalo ( 2015-07-31 15:36:45 +0300 )edit

If I understand correctly, the originals are not compatible batteries, but the very same battery. For compatibles it's a different matter of course, but if they are safe for HTCs I don't see why they shouldn't be for Jolla.

Giacomo Di Giacomo ( 2015-07-31 17:00:10 +0300 )edit

@simo I don't think we will get an answer from them. After all they already told "Not from Jolla = warranty void". Anyway, from a technical PoV the HTC ones are save. Just make sure to ship your phone with the original battery if you ever need to do a warranty repair/exchange... ;)

V10lator ( 2015-08-01 11:09:42 +0300 )edit

let's just see. I think Jolla will provide us either the official spares or information for compatible ones, if they are standing behind their words . Desire 310 originals and compatibles seems promising, an official statement on those might be different than the one currently shared: "we never recommend..."

simo ( 2015-08-01 11:49:01 +0300 )edit

answered 2015-08-03 02:07:50 +0300

Edz gravatar image

updated 2015-08-03 03:05:32 +0300

[Not an answer as such but more for visibility], I have just purchased a Polarcell battery for HTC 310/Jolla, based on the first few answers/comments of this thread.

I already have a Polarcell battery for my Nokia N900 and I'm pleased with the performance so far.

The HTC/Jolla Polarcell battery is from Wannsee-Electronic on eBay, delivered to my door for £10.03 (€14.29) each from Berlin, Germany, free P&P (worldwide with exclusions).

Link http://www.ebay.co.uk/itm/PolarCell-Battery-HTC-Desire-310-D310N-B0PA2100-BA-S960-Battery-/391182503062?hash=item5b144b4c96

Product Size: 63 x 50 x 5 mm (same as Jolla)

Product weight: 39 g (Jolla battery @ 37.7g according to my digiscales)

Capacity: 3.8 volts @2100mAh (same as Jolla)

The battery should be here in around 10 days time. I'll run some basic tests when I get it and report back here.

image description

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Got mine today: https://picload.org/image/ipopppg/ss20150803-180050-104.png

//EDIT: It seems to be a tiny bit more big than the original battery but everything still fits good.

//EDIT2: The screenshot was taken right after first boot with the battery. It arrived 50% charged.

V10lator ( 2015-08-03 19:15:42 +0300 )edit

Over night the PolarCell battery dicharged. Recharged to 100% : https://picload.org/image/iplaawa/ss20150804-092649-669.png

Does anyone know why the secon test failed, for me every value looks golden?

BTW: Battery temperature was very stable (+/- 1° C) while charging. Couldn't feel any heat with bare hands so I think this wasn't some sensor issue).

//EDIT: When the phone discharges a bit (to around 97%) the test Value falls low enough for the test to pass. So I guess the test failing is caused by the PolarCell battery being better than the Jolla one (8.16Wh vs. 7.98Wh).

V10lator ( 2015-08-04 10:46:19 +0300 )edit

Hmmm, interesting and a little disappointing as well. I wonder if you have a dodgy/faulty battery or the battery is simply not suited for use in the Jolla. Thanks for feedback, keep it coming! :)

Edz ( 2015-08-04 11:17:17 +0300 )edit

Disappointing? Depends on how you interpret the data. For me it looks as the PolarCell reports a maximum capacity of 8.16Wh. That's more than the original Jolla battery provides (7.98Wh) but the phone charges it up to that capacity just fine, so hardware on both ends works fine. The only fault is the test freaking out as the capacity breaks a hardcoded value ("Design maximum"). ;)

V10lator ( 2015-08-04 11:54:42 +0300 )edit

I see what you're saying now. I misunderstood your opening line; "over night the PolarCell battery discharged.....", that was what caught my interest, wondering why or how it dishcarged so quickly.

Edz ( 2015-08-04 12:12:15 +0300 )edit

answered 2015-07-30 09:16:02 +0300

Henque19 gravatar image

I think the main problem with finding replacement batteries is that Jolla chose to use so called High Voltage LiPo batteries. They can safely charge to 4.35V instead of 4.2V for regular LiPo batteries. That is a good decision, since the battery can hold more energy but it makes it a lot harder to find replacements.

I have not found any source for HV LiPo that have the same form factor as a Jolla battery, only found a 2-cell pack made for R/C helicopters: http://www.hobbyking.com/hobbyking/store/__51507__Turnigy_Bolt_2400mAh_2S_7_6V_65_130C_High_Voltage_Lipoly_Pack_LiHV_.html But if you buy that one and remove one of the two cells it should be possible to just plug it in to the terminals on the phone (the third terminal is for battery temperature, not needed) and have it work. The problem is fitting it into the battery compartment...

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Where did you find that info? The label on my Jolla battery clearly says Li-ion, in two places.

eson ( 2015-07-30 10:55:11 +0300 )edit

You're right, my bad. Jolla uses HV Li ion batteries. But the point is the 4.35V charge voltage limit that makes it hard to find a good replacement. I think a 4.35V Li ion battery and a 4.35V LiPo can be charged in the same way, but charging a 4.2V battery (either chemistry) to 4.35V will degrade it very quickly or in the worsk case catch fire.

So as long a anyone can find a 4.35V battery, we should be good. Doesn't really matter if it's LiPo or Li ion.

Henque19 ( 2015-07-30 15:36:10 +0300 )edit

Look at these pictures. This is the battery discussed in this thread, and the battery label says "Limited Charge Voltage: 4.35V +/-0.05V". I will soon be able to tell you if it fits the phone to.

eson ( 2015-07-30 18:25:13 +0300 )edit

hi, i've just checked the picture of an HTC Desire 310 battery and it definitely says 4.35 V so i think the chances are very high that this is the one. i did order one yesterday for 14 Euros incl. shipping and several other did too. so soon we will now

pawel ( 2015-07-31 12:54:09 +0300 )edit

Checking on eBay, HTC Desire 310 batteries are indeed HV 2100 mAh and listed as being 63 mm × 50 mm × 5 mm. Looking good! Let's just hope some company in Europe can get it sent through the mail, unfortunately many post offices have recently refused to carry "bare" lipo batteries not inside consumer electronics (China Post doesn't refuse, they just throw them away without telling anyone).

ExTechOp ( 2015-07-31 16:18:17 +0300 )edit

answered 2015-07-30 12:27:25 +0300

arie_jolla gravatar image

updated 2015-07-30 12:32:35 +0300

From another post here on together.jolla.com where people seem to have found a valid replacement battery.

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as above;

image description

Edz ( 2015-08-03 02:39:21 +0300 )edit

answered 2015-07-31 13:37:44 +0300

pawel gravatar image

i think that Jolla knows if they are using same battery as another brand or not or they could at least be able ask their producer maybe it is again a legal thing ;-) however it would be great from Jolla to confirm that an HTC Desire 310 battery will not break the phone

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I don't think Jolla knows this for sure. I believe their manufacturing company picked the model.

Giacomo Di Giacomo ( 2015-07-31 15:21:09 +0300 )edit

still they could have asked the manufacturing company people were asking for it for more then a year

pawel ( 2015-07-31 20:53:52 +0300 )edit

answered 2015-08-02 19:01:55 +0300

viskari gravatar image

maybe this would fit http://www.tradera.com/item/343303/232033622/htc-desire-310-3-8v-2450mah-uppladdningsbart-li-polymer-batteri

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Not sure if you have read the above answers, but people allready found out that the HTC Desire 310 battery fits Jolla and might actually be the same very one Jolla uses.

jollailija ( 2015-08-02 20:12:19 +0300 )edit

Personally, I don't trust those Chinese gold wrapped batteries, too many bad reviews. They seem to be re-labelled old batteries.

I found this swedish reseller that I've tried: http://www.teknikdelar.se/batterier/mobilbatterier/htc/htc-desire-310-batteri-original/

Seems legit, I'll report back when I get the battery...

Henque19 ( 2015-08-03 10:49:38 +0300 )edit

The Chinese gold batteries are newly manufactured but with cells that have less capacity than the originals (A-grade rather than AAA-grade that is used in originals and in the best compatibles). Nevertheless I ordered one of those, so when I get it I will test it and report, but I am 99% sure that it works although you will probably be better off with Polarcell or original HTC batteries.

Giacomo Di Giacomo ( 2015-08-03 12:04:40 +0300 )edit

Hmm, some might be new but the quality will vary I think. The capacity printed on the label is most definitely wrong.

Henque19 ( 2015-08-03 12:49:42 +0300 )edit

Yes, the capacity is false, of course.

Giacomo Di Giacomo ( 2015-08-03 13:41:40 +0300 )edit

answered 2015-07-30 15:11:49 +0300

simo gravatar image


Don't vote this answer, but instead select one of the 5 comments below and vote it up

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I don't think I will need a spare battery within the next 3 months

simo ( 2015-07-30 15:12:20 +0300 )edit

I'd buy a spare battery from Jolla Shop (only) for 25€ within the next 3 months

simo ( 2015-07-30 15:12:34 +0300 )edit

I'd buy a spare battery from Jolla or 3rd party for 25€ within the next 3 months

simo ( 2015-07-30 15:12:49 +0300 )edit

I need one even faster, and I'm prepared to pay even a bit more

simo ( 2015-07-30 15:13:07 +0300 )edit

I need one, but the price should be less than 25€ for me to buy

simo ( 2015-07-30 15:13:14 +0300 )edit
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Asked: 2015-07-29 20:12:41 +0300

Seen: 3,705 times

Last updated: Aug 14 '15