Recharging li po batterys

Thread Starter

geoffers

Joined Oct 25, 2010
322
Hi all,
I've just got some 3.7v single cell lipo battery's, the data sheet is a bit chinenglish?
They have a r5402n101kd-tr-f in the pack which protects from over current ,over charge.
It says supply for that ic is up to 12v , max charging voltage for the battery is 4.20 v +/-0.05v
I'm still not sure how to charge them, can I use a 5v wall wart type thing which is easy to get hold of and leave the on board ic to sort it all out, or do I need to include a lipo charging ic in my circuit to make sure the battery charges safely. Most of the ones I have seen need around 6.5v supply though, not as common as a 5v phone charger/USB etc.

Thanks Geoff
 

Attachments

JWHassler

Joined Sep 25, 2013
284
Would be better to see the datasheet of the charger, rather than its constituent IC.
That said, is it something like this?
I've bought a few of these, and they just work. Connect 5 volts an go.
But *don't* get the one with a 'mini-B' connector: you want 'micro-B'
 

Thread Starter

geoffers

Joined Oct 25, 2010
322
Hi,
Thanks for the reply, not quite like that, the ic I attached the data sheet for is built into the battery, those boards do look neat tho!

I was just trying to decide if its safe long term to charge at 5 v or if I need to add something else to control the charge.
It looks to me like it ought to be OK, but I had a friend a few years ago who used to charge lipos for model planes under a up turned dustbin with two concrete blocks on top for when they exploded.....
Cheers Geoff
 

Thread Starter

geoffers

Joined Oct 25, 2010
322
Thanks,
I had a look at that, google translation is pretty good, still not 100% sure that the Ricoh chip in my battery will allow me to charge with a 5v supply?
I might try it , I've flattened one now, rang Darnell tech support here in UK and the chap said, don't know!
Cheers Geoff
 

Thread Starter

geoffers

Joined Oct 25, 2010
322
Thanks Dave ,
I've just been going through the data sheet again and read this bit...

After detecting over-charge voltage or over-charge current, if the battery voltage is lower than over-charge
detector threshold voltage, the R5402N101KD can be reset and the output of COUT becomes “H” when a
kind of load is connected to VDD after a charger is disconnected from the battery pack. If a charger is
continuously connected to the battery pack, when the cell voltage becomes equal or lower than the release
voltage from over-charge, over-charge will be released and COUT becomes “H”.

I guess this means I'm pretty safe for 5v charging? Those little 5v USB chargers are everywhere and convenient :)
Cheers Geoff
 
Top