Help! Protection Circuit!

Kurt_ · Post by **Kurt_** » Mon Nov 28, 2005 5:32 pm

Hello. I need to make a protection circuit for 2 of these batteries in series:

http://www.batteryspace.com/index.asp?P ... rodID=2169

they're 3.7v, 6150mAh

I have no clue what to do, if I could give any mroe information I would.

Somebody please help!

Turbo Tax 1.0 · Post by **Turbo Tax 1.0** » Mon Nov 28, 2005 5:33 pm

i bought some of these batteries about a week ago and they havnt gotten here yet. i would say just buy the smart charger and you will be fine

Kurt_ · Post by **Kurt_** » Mon Nov 28, 2005 5:38 pm

And how would a charger help me make a protection circuit?

And any other battery ideas for around 50$ or less.

What did you use for batteries in your SNESp and how long do they last you?

Turbo Tax 1.0 · Post by **Turbo Tax 1.0** » Mon Nov 28, 2005 5:44 pm

i used some nice Ni-MH AAs i got from ebay that were 2500 ma they give a pretty good life, 2 and a half hours about

Kurt_ · Post by **Kurt_** » Mon Nov 28, 2005 5:48 pm

Cool. How many did you use?

Would 2 packs of these do? (4 wired in series, then 2 'packs' in parallel)(2100mAh Mi-MH)

http://www.thesourcecc.com/estore/Produ ... ct=2318313

I'm just full of questions today!

My apologies.

Turbo Tax 1.0 · Post by **Turbo Tax 1.0** » Mon Nov 28, 2005 5:53 pm

dont buy those they are way to expensive i got at least 24 AAs for that price on ebay and they are more powerful, you could also but a 7.2 volt rc car battery pack from radioshack with a charger

Kurt_ · Post by **Kurt_** » Mon Nov 28, 2005 5:57 pm

You mean this?
http://www.thesourcecc.com/estore/Produ ... ct=2300430

still pretty damn expensive. I'm looking on ebay, but all the high mAh batteries are in Hong Kong or England or something (2500+)

Meh, I'll keep looking.

Other than AA's, have you used any good kinds of batteries?

(This is my last question for now, thanks for the help)

P.S. - How many volts are you using, and did you keep the 7805 regulator?

cennar · Post by **cennar** » Mon Nov 28, 2005 6:54 pm

those 7.2 car battrys are vary nice. i would go with that.

Turbo Tax 1.0 · Post by **Turbo Tax 1.0** » Mon Nov 28, 2005 7:46 pm

if you live in the U.S. go to adio shack they are much cheaper there and they just got some 3300 ma rc batteries

Post by **marshallh** » Mon Nov 28, 2005 8:51 pm

http://www.towerhobbies.com

Enough said. I wouldn't even bother with Radio Shack.

timmeh87 · Post by **timmeh87** » Mon Nov 28, 2005 8:54 pm

turbo - if you use those batteries you will still need a protection circuit. the smart charger may charge the batteries safely, but with nothing controlling their discharge, they will probably explode next time you charge them, regardless of how "smart" the charger is.

once again, everyone:

if you overcharge lithium batteries, they may explode
if you discharge them past 2.9v, they may explode next time you charge them
if you draw too much current they may explode

Post by **marshallh** » Mon Nov 28, 2005 8:58 pm

If you aren't worried about the flammability of li-ion batteries, then you should. Lithium BURNS when it touches water. Basically, if you pour water on it, it's like pouring gasoline on a fire.

I'd still reccommend Ni-MH cells over Li-ion any day (Li-ions deteriorate starting the day they leave the factory.)

Turbo Tax 1.0 · Post by **Turbo Tax 1.0** » Mon Nov 28, 2005 9:37 pm

timmeh87 wrote:turbo - if you use those batteries you will still need a protection circuit. the smart charger may charge the batteries safely, but with nothing controlling their discharge, they will probably explode next time you charge them, regardless of how "smart" the charger is.

once again, everyone:

if you overcharge lithium batteries, they may explode
if you discharge them past 2.9v, they may explode next time you charge them
if you draw too much current they may explode

damn it all i guess i will have to either buy pr make a protection circuit now

maybe i'll ask gamey he used em before

iEDIT: i think i will use this do you guys see any problems, and does anyone know if i can play while the batteries are charging if i use the smart charger and this

timmeh87 · Post by **timmeh87** » Mon Nov 28, 2005 10:20 pm

what? theres no link...

Turbo Tax 1.0 · Post by **Turbo Tax 1.0** » Tue Nov 29, 2005 6:18 am

damn it sorry

here it is
http://www.batteryspace.com/index.asp?P ... rodID=1342