how to jump charge this li-on tablet battery ??? - Page 1
Forum section: electronics / repair

author: administr4tor
author_rank: Contributor
timestamp: November 19, 2015, 05:56:15 pm
content: dEVICE-https://www.ifixit.com/Teardown/BlackBerry+PlayBook+Teardown/5265Problem:-One discharged battery needs to be charged little bit with external dc power supply.Background :-This is a playbook battery, Blackberry playbook are the sh*t because once the battery goes below certain level of charge then the charging will never start unless you give charge from external power supply, so I forgot to charge this blackberry playbook and it got discharged and then i didnt use it for months and now it wont even charge and turn on.I manage to find another charged(SCREENSHOT) blackberry playbook battery from and found the pinouts and voltages but when I give external DC Power of 3.9V or 4.0V to *discharged battery* then NO CURRENT is flowing, which means that it is not charging with external dc power supply,so how can I charge this BAttery by external power supply?I have tried all the + and - supply from the pinout but no current is flowing from DC power supply to battery, I have tried several volt ranges from 3.9v to 4.2v on DISCHARGED BATTERY.Usually I charge almost all tablet and phones batteries with external dc power supply but this battery is a hard nut.Thank you

author: administr4tor
author_rank: Contributor
timestamp: November 23, 2015, 06:57:33 pm
content: no one??

author: miguelvp
author_rank: Super Contributor
timestamp: November 23, 2015, 07:09:01 pm
content: No idea, but a search on the interwebs pointed me to this:https://supportforums.blackberry.com/t5/BlackBerry-PlayBook/Battery-0-and-does-not-charge-at-all/td-p/1682953At least it fixed it for the person asking the question.Edit: adding quoteQuoteand PSQuoteThis is using the playbook charger it seems.

author: KL27x
author_rank: Super Contributor
timestamp: November 23, 2015, 07:12:30 pm
content: Where are you applying your power?It looks to me like you ought to put your 4V source on the 2.73V terminal. Either one.Until the voltage gets over 3.3V or so, you might want to limit current to 10-20mA.

author: Howardlong
author_rank: Super Contributor
timestamp: November 23, 2015, 10:12:12 pm
content: For my sins at one time I did some development on Playbooks, and one of its quirks was indeed that it apparently does die when the battery is very low. I say "apparently" because all that's needed are a nice dose of patience and a proper 1.5A USB DCP charger such as that supplied (the one supplied says it's 1.8A). A bog standard USB port or charger wouldn't ever work for me as far as I could ever tell once it'd got itself into a very low energy state.You have to leave it for quite some time under charge, but eventually it will recover. I can't remember how long it was on charge the first time this happened to me, but I'd forgotten about it and had given it up as broken. Anyway, miraculously when I came by it again some time (possibly a day or two) later after being on charge, it booted up.Now today I can't remember the last time I powered up my Playbook, it's many months, but I took the opportunity just now to power it up and charge it up, but coincidentally and ironically, sadly the magic smoke has just escaped out of the original Playbook charger, one of those sealed units with little chance of redemption without engaging a Dremmel, so it's now headed for landfill.Despite those many months of doing nothing in a drawer (after that first time, I always fully switched it off rather than leaving it in standby) it started up without any need for charging after all, but I am now topping it up on a different DCP port at just shy of 1.5A anyway!

author: amyk
author_rank: Super Contributor
timestamp: November 24, 2015, 04:55:17 am
content: Note that lion cells should not be reused if they've gone below ~2V for any significant length of time, and 3V is a more comfortable safe minimum voltage for them.

author: donkey77
author_rank: Regular Contributor
timestamp: November 24, 2015, 07:19:47 am
content: I've got a couple of these and have had the same problem. Forget the USB charge and get a portable fast charger (not the desk stand type), the magnetic holder one, this allows you to charge and use USB for data at the same time. Connect the the charger, leave for ten seconds, remove and repeat, maybe 50 or more times. Eventually enough power goes in that the charging circuit with control it.Unfortunately no bugger really supported it and now even things like YouTube don't work properly but the screen is good and with 64 gb mine just get used for kids in car films.

author: administr4tor
author_rank: Contributor
timestamp: December 04, 2015, 04:59:09 am
content: Quote from: KL27x on November 23, 2015, 07:12:30 pmI have applied voltages between all + and - pinouts of the battery.

author: senso
author_rank: Frequent Contributor
timestamp: December 04, 2015, 09:33:45 am
content: Remove the plastic, find the LiPo terminals, charge there, right into the battery, going from the outside you are still getting blocked by the protection circuitry, done that dozens of times in Asus tablets..