Sony Ericsson's BST-33 Li-Polymer batteries swelling into a lawsuit?
By Thomas Ricker 
posted January 28th 2009 7:31AM
posted January 28th 2009 7:31AM
We've seen plenty of swollen and exploding batteries 'round here, but this is the first Li-Polymer battery (a technology generally assumed to be more stable and less prone to swelling and fire than Li-Ion) that we can recall ballooning into such a possible danger. Reader Christian sent us these pics of what's normally a 4-mm thick battery (pictured right) inside his W880i handset now swollen to a full 7-mm. The BST-33 sits at the heart of a long list of SE phones, a list we've included after the break along with one more picture. Do let us know if you're seeing similar issues.
List of compatible Sony Ericsson phones: C702, G502, K530i, K550im, K800i, K810i, M600i, P1i, P990i, W300i, W302, W595, W610i, W660i, W705, W850i, W880i, W950i, W960i, Z320i, Z530i, Z610i, Z750i
Happened in my w810i. Replaced it with an obvious fake battery, and its working great so far...
Quite strange indeed. I've been using Li-Po batteries in SEs from the days of the T68i and have a P1i and Xperia right now without a single problem so far. Haven't heard of a single problem like that on any of the major SE forums around.
my wife uses the w810i and have had no problems at all with that battery, just the k800's blew up
Happened with my K500i, replaced it with a cheapo one, opened up my phone a year later, hasn't worked since.
My z610i has a BST-33 and it show no signs of swelling.
I've had it since November 2007.
Same thing happened to my Sony W880i Walman phone. Had to replace battery, and phone was never quite the same after I started noticing the swelling. Too bad, as I loved that phone (up until I upgraded to an iPhone, which itself is not immune to all disasters)
Original batteries in both P990i (Voda) & K800i (Virgin) UK phones bought in Aug/Sept 06 and no issue with either one. Still hold a charge as well as day 1 believe it or not. Used every day and charged 2/3 times a week in Canada. All is (s)well so far.
yep has happened to my battery
I'm on my 3rd SE ATM and I haven't have any problems of the sort. Ah, I love my C905. :P
Happened to me too, same battery, same phone. I'm on my old Nokia now while I'm waiting for the new battery to arrive.
My W700i had a similar issue where the battery swelled up to twice the size! Surprisingly it had little impact over the phones performance!
I used it for almost 18 months and had to switch only because I lost it somewhere!
I have here next to me a swollen BST-36 :(
My Battery has gone like a ballon too... I upgarded to the c905 and put me k810i aside..... went to look at it about a week or so ago and it was swallen.... i orderd a new one but have kept the old one just incase some one wants to see it.......... stupid thing
I have four of these batteries (k790, k800, c702 + 1 extra i forgot to give back when i returned my first k790). all original. all in perfect condition. i charge em for a couple hours after i get home, unplug it before i hit the sac, and i'm good to go for a couple of days! there will always be QC issues in any line of products.
Happened to me with an old iMate (made by HTC), a Vodafone-branded Sharp and a Motorola V3i. No problems with batteries in my old Nokias, SEs or Samsungs.
My understanding is Li-Po batteries are much less stable than Li-Ion. Go ask any RC helicopter or airplane hobbyist. Some even charge Li-Po's in a ceramic pot.
She's gonna blow!
I had a W880i sitting in the cupboard, unused for about 8 months. The battery swelled so much the back of the casing had popped off. I threw it out about 2 weeks ago, should've kept it.
My old W880i did that just around/after the Dell exploding battery incident. I took it back to the phone shop and they weren't interested in solving, so bought a $3 one off ebay, which was probably some knock off battery copy, but didn't have a problem with that one!! Probably 'cos it wasn't made by Sony ;-)
I had this problem with the battery in my k800i
I gave the battery to a waiter in a noodle restaurant and bought a new one on the way home.
I am an R/C hobbyist, use Lipo batteries only.. I have had a cell swell similar to this but much more severely. It was a 4000mah 3.7v Maxamps cell. one out of the 3 cells in the battery. I simply removed it from the rest of the pack and discarded it. Lipos swell and do catch on fire. it happens more than you might think.
I currently own the SE T700 and it also uses the BST33 version. So far no problems, maybe Ill keep an eye out and check once in awhile. My other sony phone had no problem though it didnt use this specific cell.
No swelling in the one on my european K550i.
No swelling of a 2+-year-old BST-36
i would say the main problem is the difference in the shape of the battery on the left, as the plastic bottom is more reminiscant of the k750 style battery(not sure on the numbering here)
the bottom is not as rounded on the sides, and the plastic at the top is somewhat suspicious.
I have the same problem, my battery is now 7mm thick!!
I have the z525a and my battery looks just like the one pictured. Should I not be keeping it in the nightstand next to my bed?
Well I've just located my spare Dell Latitude 600m Li-Polymer battery and it has swelled up too... and no it's not one of the Dell recalled ones... anyone else noticed their "old" Dell batteries putting on a little weight after the holidays?
same here yesterday only my battery got swell... what to do..