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Chris Briggs
26-01-2010, 11:11 PM
Just a quick one chaps, what is the maximum voltage for a 2S lipo - is it 8.2 or 8.4V? The instructions I got with the battery say 8.4V (or 4.2 / cell) but when i charge, the charger stops at 8.2V.

Its a new charger and pack (my first Lipo) so I presume everything is ok, just wondering why the difference.

Ta
Chris

MikeS
26-01-2010, 11:17 PM
Should be 8.4v for 2S LiPo. Check the battery voltage with a volt meter to see what that says, then check the chargers configuration as many support different cell type and it might be wrong.

Chris Briggs
27-01-2010, 08:50 AM
Mike

Thanks for the reply, the pack is at 8.2V after charging - checked on a digital multimeter. The charger is set for LIPO but I cant find any setting to adjust the ultimate pack voltage - you select 1,2,3,4,5S pack type. I am sure it wont affect me too much - I am only running stock brushless and aint very good even at that. I was just curious and wondered if 8.2V was standard and 8.4V was the limit.

i will have another look tonight to see if i can find a hidden setting!

Regards
Chris

Dez82
27-01-2010, 10:40 AM
Hi Chris, 8.4V is the maximum, not a target, and some budget LiPo chargers only charge a 2S LiPo to 8.2V to give the cheaper LiPo cells a longer working life, so it might just be that.
Some more expensive and accurate chargers have a cold weather balance that reduces the cell voltage to accomodate the LiPo technologies hate of cold temperatures, so it might be that.
What charger are you using by the way?

Chris Briggs
27-01-2010, 02:19 PM
Dez - ha, your email makes sense when you as the make.... I guess you hit the nail on the head, it is a "budget LiPo Charger" but I will have another look at it tonight, it may be a setting I am missing or something like it is limiting the voltage due to the balance lead being plugged in. Your mention of 8.4V being a maximum kind of answers my question, I am not one for pushing things to the limit all the time anyway!

MikeS
27-01-2010, 02:26 PM
Question:

...what is the maximum voltage for a 2S lipo...
Answer:

Should be 8.4v for 2S LiPo.

:rolleyes:

Chris Briggs
27-01-2010, 03:15 PM
Sorry Mike I did note you said 8.4V as well! :cool:

KeithA
27-01-2010, 03:57 PM
My guess is that your charger is in Li-ion mode instead of Li-Po mode.

Max charge voltage for Li-Po will probably be 4.2V but for Li-ion it could possibly be 4.1V, so that stacks up with your 8.2V reading.

MikeS
27-01-2010, 04:13 PM
.....then check the chargers configuration as many support different cell type and it might be wrong. :rolleyes:

Mark Christopher
27-01-2010, 05:03 PM
dont worry mike, i saw what you put so did not reply LOL

Chris Briggs
27-01-2010, 05:19 PM
DAM DAM DAM you are all correct! despite me being positive it said LI-Po, it did, when I turned it back on, in fact say LI-Io

My mistake, I hang my head in shame and vow never to be an idiot again.

Thanks for your help guys, I await your replies giving me appropriate slagging.


Chris

PDW
27-01-2010, 10:23 PM
My mistake, I hang my head in shame and vow never to be an idiot again.

ChrisDamn - you shouldn't promise what life will make sure you can't deliver!! :D :D Glad it's sorted...

Chris Briggs
04-02-2010, 08:25 PM
Not wanting to ask another silly question but we dont always get what we want so here goes!!

Has anyone ever seen or heard of issues with storing lipos at low temperatures? I keep all my racing kit in the loft and it can get quite cold up there - I mean 2 to 3 degC as I am in North Scotland. I can see maximum temperatures all over the place but nothing about low temperatures. I am keeping them in the dining room at the moment but the missus does keep commenting that they could go in the loft!

THanks