Acronyms

[Studeman]

I am having a difficult time understanding some of the acronyms used when battery packs are being discussed. "20C", 30C", etc. I assume means 20 degrees C, am I right?

What about "6S", "8S"?

Is there's a place here on E-S where I can find this? I went to the Wiki link, but it didn't have what I was looking for.

Thanks in advance for any help

P.

 

[spinningmagnets]

Imagine you have 4 batteries that each have 12 volts, and 15 Amp-hours of size. If you hook up two of them with one positive post to one of the negative posts, you would have a two battery SERIES string that was 24V and 15-Ah.

If you connected them positive to positive, and negative to negative, you would have a two battery PARALLEL string that was 12V and 30-AH.

P or S describes how many are connected either in series or parallel. Using 4 batteries at 12V / 15-Ah each, you could have:

4S1P would be 48V / 15-Ah

1S4P would be 12V / 60-Ah

2S2P would be 24V / 30-Ah

LiFePO4 cells average 3.2V per cell, the Ah size is dependent on the physical size.
LiPo and LiMn average 3.7V per cell

the C-rate has to do with how much CURRENT it can produce, but I am not good at describing that the proper way.

 

[TMaster]

6S = 6 individual cells in a series formation. (Example: 3.3V per cell X 6 with 3Ah capacity) = 19.8V & 3AH
6P = 6 individual cells in a parallel formation. (Example: 3.3V per cell with 3Ah capacity X 6) = 3.3V & 18AH
6S6P = 36 cells total, 6 parallel formations of 6 cells wired series. (Example: 3.3V X 6) & (6P = 6 X 3AH) = 19.8V & 18AH
6S6P = 19.8V X 18Ah = 356.4 Whr (Watts per hour)

Another example is my setup:
6S3P + 6S3P + 6S3P + 5S3P packs wired in series again for 23S3P or 75.9V

Example with 30C Rated
3 Ah x 30C = 90 Amps constant rating of current draw.

I would suggest googling some of this stuff, or searching on here

 

[Takemehome]

With spinningmagnets exemple cell:
rated at 1C: you can pull 15AH for an hour.
rated at 2C: you can pull 30AH for 30 minutes ( 30AH X 0.5 Hour = 15 Amps )
at 10C: 150AH for 6 minutes ( 150AH X 0.1 Hour= 15 Amps )

If you ride at 1/3C you can ride for 3 Hours ( 5AH X 3 Hours = 15 Amps )

 

[999zip999]

What do you need a battery for ?

 

[Studeman]

1st Thanks for the Turtorial!!

What do you need a battery for ?

I'm building my knowledge base before I start spending $$.

I have what I would call a good working knowledge of DC Electrontics and know the difference between Sieres and Parallel and am somewhat embarassed that I didn't figure out the P and S designations

My ultimate goal, at least in the short term, will be to build a bike that can go at least 20 miles at >25 MPH with a top speed of 30 MPH, and these are unassisted speeds by my ageing and acheing legs

Thanks again!

P.

 

[jonescg]

6S = 6 individual cells in a series formation. (Example: 3.3 V per cell X 6 with 3Ah capacity) = 19.8 V & 3 Ah
6P = 6 individual cells in a parallel formation. (Example: 3.3 V per cell with 3 Ah capacity X 6) = 3.3 V & 18 Ah
6S6P = 12 cells total, 6 in series and 6 in parallel. (Example: 3.3 V X 6) & (6P = 6 X 3 Ah) = 19.8 V & 18 Ah
6S6P = 19.8 V X 18 Ah = 356.4 Whr (Watt hours)

Another example is my setup:
6S3P + 6S3P + 6S3P + 5S3P packs wired in series again for 23S3P or 75.9 V

Example with 30C Rated
3 Ah x 30C = 90 Amps constant rating of current draw.

I would suggest googling some of this stuff, or searching on here

Just corrected some of your SI units. The product of W and time is Wh, or watt-hours. A Watt per hour is the same as a Joule per second per hour. Which doesn't make sense

 

[TMaster]

Thanks, I'm not a EE, but I tinker

 

[amberwolf]

http://www.endless-sphere.com/w/index.php/Terminology_and_Explanations_of_Common_Misconceptions

http://www.endless-sphere.com/w/index.php/Acronyms

 

[Chalo]

http://www.endless-sphere.com/w/index.php/Acronyms

KFF is not in there. That's the one I learned here first.

 

[TMaster]

http://www.endless-sphere.com/w/index.php/Acronyms

Nice list! I learned some things, and the list needs some more things.

 

[dogman dan]

Yeah, and I don't seem to be enabled to add any.

Needs KFF, WH and WH/MI. And no doubt some others.

 

[hjns]

what about mph, kmh, oC, kv, HT, HS, kma, wtf, iirc, lmao, url, img, etc.....

 

[Ypedal]

how about the FAQ

http://endless-sphere.com/forums/viewtopic.php?f=14&t=26621

 

[999zip999]

Studeman you should look at a 48v or 16s lifepo4 battery with a 5c or better. Just plug and play. Lot's of good reading here. So only time will iron it out.

 

[Kingfish]

You guys forgot one other explanation for Batteries:
S, P, C = yes those are correct

Often times though you will see on a Battery Spec sheet that has two C ratings; Example: 15/2C

• The first number is the Discharge Rate, and the second number is the Charge Rate. Therefore if I have a battery that’s 6S1P 5000 mAh 15/2C LiPo, it means that it can discharge at 15X, and recharge at 2X ->
• 15 x 5 = 75A/h Discharge, and
• 2 x 5 = 10A/h Recharge.
• Figure LiPo to be 4.2V/cell at maximum, 6 x 4.2 = 25.2V
• Discharge = 75 x 25.2 = 1890W/h
• Recharge = 10 x 25.2 = 252W/h

These factors are important for calculating instantaneous power as well as the time to recharge, or more importantly - the size and capacity of the charger. :wink:

Did I get my units right? I always seem to miss something there...

Anyways... I am keen on the recharge rate when I go cross-country because I carry a lot of batteries, so the battle for me is finding a fast, powerful quiet charger. :lol:

Cheers, KF

 

[amberwolf]

Everyone is welcome to add to the wiki pages; just make sure you are logged in (using your ES username and password). AFAIK the only members that can't are ones with non-alphanumeric characters in their names, until MRVass gets that fixed.

 

[Studeman]

http://www.endless-sphere.com/w/index.php/Acronyms

KFF is not in there. That's the one I learned here first.

Chalo,

What IS KFF?

 

[999zip999]

KFF is one you will never forget.

 

[Ypedal]

Kentucky Fried Fingers

 

[Toorbough ULL-Zeveigh]

acronym, isn't that the irrational fear of big words?

wow, that wikis full of gems such as 'NIMBY' while blissfully ignoring basics like 'I = current' & 'E = EMF/electromotive force/voltage'.
(which differs from the units of Aisforamps & Visforvolts.)
if you're gonna include non-electric acronyms then we're gonna need a whole separate section just to make it thru philistines posts ATM, DAP, MSOG.


not to nitpick (well,maybe).
battery electrochemistries derive their nomenclature from the periodic table.
NiCd & NiMH are the proper descriptors not Nicd or Nicad & Nimh.
anyways my physics prof would mark it wrong if you did.

also KFF shouldn't appear in the wiki at all.
it's a badge of honour you earn or at least should have to do the reading to find out for yourself.

btw, pop quiz hotshots;
anyone know why its the letter 'i' for current, what is the full word?

 

[full-throttle]

btw, pop quiz hotshots;
anyone know why its the letter 'i' for current, what is the full word?

Intensité (de courant)

 

[full-throttle]

'I' was already taken

Why the letter 'L' was chosen is explained in wiki

It is customary to use the symbol L for inductance, in honour of the physicist Heinrich Lenz

 

[Toorbough ULL-Zeveigh]

thanx for that, i assume you're quoting from the actual real wikipedia.
i'm referring to these missing from the acronym list ESwiki.

almost forgot to mention that internal resistance is Ri, not IR.

pushing my luck for one more, why Z=impedance?

 

[Ypedal]

french

Resistance Interne