Homemade Battery Packs

Batteries, Chargers, and Battery Management Systems.
cheys03
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Re: Homemade Battery Packs

Post by cheys03 » Apr 12, 2014 11:55 am

dnmun. You must be joking.
DrkAngel has repeatedly produced evidence to back up all aspects of his testing strategy. Evidenced success with numerous packs and thousands of cells weened down to the ones most suitable to each application.
eBeach has stated that the bleed down test's usefulness depends on the intended application of the cell. He's right. However, if your intended application is an eBike battery, it is essential that fast bleeding cells are eliminated. Since this, DrkAngel has had to repeat numerous times that the bleed down test is not the only test. Why he had to repeat himself so many times is or even say it in the first place is unfathomable - as it is very, very clear from his testing methodologies that he would not ever solely rely on the bleed down test. Yet eBeach stuck to his statement like a broken record, oblivious to the obvious.

Anyway, I thought this was all over, agree to disagree everyone?

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kje
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Re: Homemade Battery Packs

Post by kje » Apr 12, 2014 12:14 pm

DrkAngel wrote: If charged to 4.20V, 4.17V cell will unbalance its bank, creating a pack requiring constant re-balancing.
John in CR wrote: kje,
If a 3.6v-3.7v nominal cell can't be charged to 4.2v then consider it a dud. You're going thru a lot of work, so you only want the best and brightest in your primary pack, because all it takes is one bad one to kill them all, so thoroughly weed out those little terrorists. It should be easy to find lots more discarded 18650's, so instead of spending effort on questionable cells, use the time to round up lots more for testing. Then you can make a nice big pack of cream-of-the-crop cells.
Thank you guys. I`ll try to find more cells for testing and avoid unbalanced banks.
I use two different chargers
1) Imax B6
2) Multifunction charger from China (ebay)

The Imax charger won`t charge this cell above 4.17V but the Multifunction charger does. As you said John in CR, I won`t spending effort on questionable cells but I just wonder... is the Imax too sensitive or does the Multifunction charger just forcing the cell?
DrkAngel wrote:Already recommended charging to only 4.10V.
3.6V cells are designed for 4.10V full charge.
Charging to 4.20V will give you, possibly 10% more capacity but cut lifespan in ½.
Yes, I`ve taken your advice to consideration. My plan is charging the finished batterypack to 4.10V after each discharge. But in my testing of almost 200 cells I charged cells to 4.20V from the beginning, so I proceed with 4.20V just this test round.

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Re: Homemade Battery Packs

Post by e-beach » Apr 12, 2014 1:51 pm

John in CR wrote:Ebeach, the part you keep missing isn't that anyone is saying all bad cells have high self discharge, but rather that all cells with high self discharge are bad. It's a perfectly valid and simple battery test....charge them all up and let them sit. Those which don't hold their voltage well go directly into the recycle bin and require no further time consuming testing.
Con respecto, I haven't missed that point at all. And from my study it is also not 100% accurate as I have found a small number of cells that self discharge and still have a very useful capacity. I use my bike on a daily basis and their-fore charge my bike on a daily basis so one option for me could include cells like that, or not depending on how many cells I have for a given pack. I won't say any more because when I post my findings, (all of which I have well documented and are repeatable,) people around here get all fluffed up and can't have an adult conversation for the betterment of all....so why bother. :roll:

When I finalize my study I will publish my complete finding someplace.

:D
Favorite Quote: "This is L.A., sugar. There is no 'over the top." --- Chris Erskine

Current build: Liahona w/ cheap front suspension and suspension seat post. Yescomusa 36v 800w generic front hub motor. 15ah Headway triangle mounted pack. Tronsung 30 amp,

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DrkAngel
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Re: Homemade Battery Packs

Post by DrkAngel » Apr 12, 2014 6:18 pm

e-beach wrote: I have found a small number of cells that self discharge and still have a very useful capacity. I use my bike on a daily basis and their-fore charge my bike on a daily basis so one option for me could include cells like that
:D
I guess I just have higher standards ...
I won't use cells that constantly unbalance my packs.

and ...
Self discharge is often progressive ... so I'd rather not use obviously defective, possibly dangerous, cells.

dnmun wrote: you are using drop in resting cell voltage as an indication of self discharge rates and you did that with absolutely no proof there is any connection between the two.
You can't be serious! ... ?

A cell, setting by itself, dropping in voltage must be self discharging ... nothing else is discharging it!
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dnmun
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Re: Homemade Battery Packs

Post by dnmun » Apr 12, 2014 11:23 pm

you don't know that and you pompous attitude when it is clear you don't know what is happening is offensive when you insult ebeach for trying to bring some reality into the thread. sure it may only be you that inhabits it but you don't have the right to insult him and bully him.

capacity of the cell is what matters. he tried to clue you in. you are stuck. get over it.

if you can prove your argument then you will. but i think he will prove you wrong first.

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Re: Homemade Battery Packs

Post by DrkAngel » Apr 13, 2014 12:22 am

e-beach wrote: I have found a small number of cells that self discharge and still have a very useful capacity. I use my bike on a daily basis and their-fore charge my bike on a daily basis so one option for me could include cells like that
:D
DrkAngel wrote:I guess I just have higher standards ...
I won't use cells that constantly unbalance my packs.

and ...
Self discharge is often progressive ... so I'd rather not use obviously defective, possibly dangerous, cells.
dnmun wrote: you are using drop in resting cell voltage as an indication of self discharge rates and you did that with absolutely no proof there is any connection between the two.
DrkAngel wrote:You can't be serious! ... ?

A cell, setting by itself, dropping in voltage must be self discharging ... nothing else is discharging it!
dnmun wrote:you don't know that and you pompous attitude when it is clear you don't know what is happening
If a battery is sitting, unattached to anything, all by itself, and it is discharging ... it must be self discharging.

Unless there is some Gremlin sticking wires on it? ... when no one is looking?
Lightening bugs recharging, behind your back?
Invisible fairies ... getting "juiced"?
A little learning is a dangerous thing;
Drink deep, or taste not the Pierian spring:
There, shallow draughts intoxicate the brain,
And drinking largely, sobers us again.

I enjoy enlightening ... and enlivening the spirit of the innovators.

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e-beach
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Re: Homemade Battery Packs

Post by e-beach » Apr 13, 2014 10:11 am

DrkAngel wrote:
e-beach wrote: I have found a small number of cells that self discharge and still have a very useful capacity. I use my bike on a daily basis and their-fore charge my bike on a daily basis so one option for me could include cells like that
:D
DrkAngel wrote:I guess I just have higher standards ...
I won't use cells that constantly unbalance my packs.
See, now there you go again..... :roll:

Where is the rest of my statement?
or not depending on how many cells I have for a given pack.
Using only part of a posters statement in a fallacious argument only self-impinges your own integrity. In other words, you make your self look bad. :(

In my studies all test data is valid data weather is works against my theory or not. If that cell exists in my experiments then it exists regardless of how I feel about it. As I stated, a small number of them exist, less then 1 in 100. Then again, I believe in balance charging and am not afraid of a bms.

In the past you have stated that:
my latest method of cell testing has produced packs of such "balance" and reliability that I do not need to balance charge or use any BMS. I merely bulk charge with a CC\CV power supply ... with excellently balanced "full" and "empty" ... equal voltages between all banks! Charging-discharging does not actively equalize the pack ... it just does not unequalize it ...I do monitor bank voltages and "fine tune" as deemed advisable.
That is a fine statement if true. Could you please post your cell by cell data as proof of this statement as I am very eager to study it.

Thanks

:D

Oh, and PS....
DrkAngel wrote:I guess I just have higher standards ...I won't use cells that constantly unbalance my packs.
DrkAngel wrote:......I do monitor bank voltages and "fine tune" as deemed advisable.

:wink:
Favorite Quote: "This is L.A., sugar. There is no 'over the top." --- Chris Erskine

Current build: Liahona w/ cheap front suspension and suspension seat post. Yescomusa 36v 800w generic front hub motor. 15ah Headway triangle mounted pack. Tronsung 30 amp,

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DrkAngel
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Re: Homemade Battery Packs

Post by DrkAngel » Apr 13, 2014 10:50 am

DrkAngel wrote:my latest method of cell testing has produced packs of such "balance" and reliability that I do not need to balance charge or use any BMS. I merely bulk charge with a CC\CV power supply ... with excellently balanced "full" and "empty" ... equal voltages between all banks! Charging-discharging does not actively equalize the pack ... it just does not unequalize it ...I do monitor bank voltages and "fine tune" as deemed advisable.
e-beach wrote:That is a fine statement if true. Could you please post your cell by cell data as proof of this statement as I am very eager to study it.Thanks:wink:
Well, 1st off ... I don't record "cell by cell" data.
After building banks that are free of self discharging and of equal capacity ...
I just bulk charge a few hundred cycles and monitor bank voltage at full and empty.

I will be posting up my 4th year - 7000+ mile "final" report on my 25.9V 25.92Ah recycled laptop cell build.
(I keep planning on retiring it but it still has much better capacity than the $400 eZip equivalent!)
I did do a balance charge on it yesterday, there was a few 100ths V variance at full charge (4.17V per bank 4.21V - 4.15V) ... it sat, unused, most of this Winter. (iMax measured 13Ah+ , but typical used is ≤ 10Ah)

Got spoiled by my 33.3V 31.2Ah Winter build!
Will build front mount for my 33.3V 43.2Ah build, between fork and bars ... too awkward for on top of rack, about 16lb.

Purchased multiple 24V brush controllers looking for 24V - 33.3V, multi-compatiblity, one has 50V caps, so looks promising ...

I will be building multiple 25.9V replacement packs for my newer eZips, - so stay tuned!
Last edited by DrkAngel on Apr 15, 2014 2:11 am, edited 1 time in total.
A little learning is a dangerous thing;
Drink deep, or taste not the Pierian spring:
There, shallow draughts intoxicate the brain,
And drinking largely, sobers us again.

I enjoy enlightening ... and enlivening the spirit of the innovators.

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dnmun
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Re: Homemade Battery Packs

Post by dnmun » Apr 13, 2014 11:22 am

"If a battery is sitting, unattached to anything, all by itself, and it is discharging ... it must be self discharging."

where is this proven? i think everybody assumes this but you use this as some sorta absolute.

but the truth is that cells which fall in voltage coming off the charger can have essentially the same total storage capacity as the cells that remain close to the charging voltage in the lifepo4 packs.

alotta people use the term "surface charge" to imply that there is some surface where these charges reside and they go back there when the cell is off the charger. but nobody knows what surface they are on.

if you build a battery without knowing the capacity of the cells in the pack you are limited to a discharge that is no greater than the lowest capacity cell in the pack.

but since you do not use a BMS then you do not have a way to know when one of the cells drops below the LVC so your presumption that the self discharge rate tells you something important is secondary to the reality that the pack is not capable of delivering all the charge that most of the cells have available.

how many of your packs can you show that have within 90% of the original storage capacity? how many get to 80% of original?

how will you prove your argument that the self discharge rate is the critical parameter to establish cell storage capacity? i have already done experiments to prove you are wrong and i know ebeach is about to do the same. i have a pouch in a pack i just built from scrap that i wrote on "cull, dropped to 3.37V right off charger" when i had first charged it up on my single cell charger but when i had finally finished analyzing the capacity of the pouches i had available, that pouch had 4.81+Ah of storage capacity. in the same range as about 95% of the pouches i tested of that type.

i have shown already that by combining a lifepo4 pouch that holds the 3.65V level off the charger, with pouches that dropped to 3.37V off the charger, that the combined pair would hold the 3.61V level and not drop more. how can you explain that? but you do not explain anything because you are working off some unknown internal mental formula you decided is how it should be done, and don't use any of the information from doing capacity testing.

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DrkAngel
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Re: Homemade Battery Packs

Post by DrkAngel » Apr 13, 2014 12:43 pm

Congratulations Dnmun!

I'm not sure what your original agenda was ... but you have succeeded in making ebeach look like a comparative genius!
At least he now, finally, seems to realize that self discharge is a factor - "small steps".
dnmun wrote: how will you prove your argument that the self discharge rate is the critical parameter to establish cell storage capacity?
1st, ebeach, somehow deluded himself into thinking this same thing, that self discharge was being promoted to determine capacity!
Since then I, and others, have repeatedly, and vehemently!, posted that self discharge has nothing to do with capacity.
You even complained about me shouting this!
Now, ... you, apparently after reading these denials repeated time and time again and again, still seem to have gotten that same delusion stuck in your head!
Do you suffer from that mentally debilitating form of myopia that only lets you see what you want to see?
Has ebeach somehow spawned some form of mental infection? ... mental constipation? ... !!!
Flush the crap out of your head!
It's too full and has covered your eyes!

Oh ... and FYI ... Lithium Iron has not been discussed here ... and is way different than Lithium ion (Cobalt).
Last edited by DrkAngel on Nov 20, 2017 7:01 pm, edited 7 times in total.
A little learning is a dangerous thing;
Drink deep, or taste not the Pierian spring:
There, shallow draughts intoxicate the brain,
And drinking largely, sobers us again.

I enjoy enlightening ... and enlivening the spirit of the innovators.

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Re: 29.6V 31.2Ah pack - in eZip Pack

Post by Laserman » Apr 13, 2014 8:31 pm

DrkAngel wrote:
DrkAngel wrote:An eZip with 29.6V 31.2Ah pack, (8s12p), without any regearing, will push to (legal - USA) 20mph capability!
With a substantial torque increase ...
Placing 29.6V eZip packs into production.
Ordered 2 iMax B8's from HobbyKing.com, 2, to save shipping.
Found 8s balance cables-connectors, might attach a 9pin serial connector to pack and use computer serial cable for balance-monitor.

I plan on building 2 - 8s 29.6V 31.2Ah packs.
Primo pack will use 96 2600mah cells that maintain 4.22-4.24V after being charged to 4.25V and left setting for 3 months.
Segundo pack will use 96 2600mah cells that maintain 4.18-4.20V after being charged to 4.25V and left setting for 3 months.
Peak charge will be 4.10V.

They make no specifically compatible controller (33.6V full charge) but I do have 1 2008 eZip that handles 24-36V, and I have modified a 12-36V 25A controller ,with deans plugs to the oem connectors, from a bad eZip controller.
So I can swap various "universal" controllers into any of my eZips.

I plan on running a heavy tinned copper braid as the power rails between banks and extending directly to the pack contacts.
Hopefully, the heavy copper braid will act as an effective heat dispersion "sink", keeping the contacts form getting too warm.
(Same tinned copper braid as used on 22.2V 41.6Ah)
Image

I'm still pondering possibilities for cooling the bike contacts as well.
Contacts.JPG
Might take a couple weeks to get chargers and cables, but should have pack ready sooner ... for test runs.

Will also have a recycled Lipo pack, or 2, or more, put together.
Gotta rebuild my 2 year old 25.9V 25.92Ah with top quality cells (and treat better 3.7V-4.05 working range), and
will build 11.1V modules in 25.92Ah, 30.24Ah, or larger?
For modular builds of 33.3V, 44.4V etc.
11.1V module as emergency power through 12V DC to 120V AC inverters.

From what I see you are using 96 cells for 33 v am I correct? I am wanting to see about building a 66v pack for my motorino
Jim
Home built mid mount with united 1kw motor
Proud owner of 2013 xpn
Hurray to justin for keeping E-S alive

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DrkAngel
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Re: Homemade Battery Packs

Post by DrkAngel » Apr 13, 2014 8:45 pm

Laserman wrote: From what I see you are using 96 cells for 33 v am I correct? I am wanting to see about building a 66v pack for my motorino
Jim
108 cells
DrkAngel wrote:Gitten-er-done!

After draining my 33.3V 26Ah (9s10p) to 33.2V, ~3.7V per bank, I marked resultant voltages and added complementary 2s to each bank as deemed advisable.
Lowest bank got the best cells - best got the worst.
Lowest bank (3.65V) got 4500mAh, highest (3.71V) got 4100mAh, the remainder apportioned in between.
Since I will discharge to not below 3.8V, where cells were within 2/100th of each other and "good" ... now they are just "more good".

At 3.8V - 4.05V capacity is still >20Ah ...
I will measure Ah capacity after next deep discharge ... though I typically recharge immediately after any use and weather is too cold for any extended rides, so, full capacity test might wait till near Spring.

Image

Last 2 banks were pulled from a different batch that had oddball tabs ... sorry, wanted it to look prettier!

I will monitor 1st few discharges ... mainly to check for bad-poor solder connections.
After that I will rely on bulk charging with the occasional balance check.

Edit - I did add 4 - 9mm, 1/2 cell height, blanks as support for the alternate banks.
And re-covered all cells with a wrap of boxing tape.
Both ends of cells were covered with closed cell polystyrene, (foam sheet, as is used for durable padding), to secure-stabilize cells tightly in pack.
A little learning is a dangerous thing;
Drink deep, or taste not the Pierian spring:
There, shallow draughts intoxicate the brain,
And drinking largely, sobers us again.

I enjoy enlightening ... and enlivening the spirit of the innovators.

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Laserman
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Re: Homemade Battery Packs

Post by Laserman » Apr 13, 2014 9:06 pm

So it would be 216 for 66 v pack correct

Thanks I may have found me a source of laptop packs and will have to see about possibly building a pack
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Proud owner of 2013 xpn
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DrkAngel
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Re: Homemade Battery Packs

Post by DrkAngel » Apr 13, 2014 9:16 pm

Laserman wrote:So it would be 216 for 66 v pack correct

Thanks I may have found me a source of laptop packs and will have to see about possibly building a pack
Any multiple of 18.
18s?p,
18s8p (144 cells) = 66.6V 20.8Ah ... if 2600mAh cells used.
18s10p (180 cells) = 66.6V 26Ah ... if 2600mAh cells used.
18s12p (216 cells) = 66.6V 31.2Ah ... if 2600mAh cells used.
18s14p (252 cells) = 66.6V 36.4Ah ... if 2600mAh cells used.
etc.
See - Latest cell testing methodology
Last edited by DrkAngel on Apr 23, 2014 5:57 am, edited 2 times in total.
A little learning is a dangerous thing;
Drink deep, or taste not the Pierian spring:
There, shallow draughts intoxicate the brain,
And drinking largely, sobers us again.

I enjoy enlightening ... and enlivening the spirit of the innovators.

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Re: Homemade Battery Packs

Post by douglashart » Apr 21, 2014 10:08 am

Drk angel, been following your thread for months now . im very newb, but trying to learn. I find your logic quite sound , despite the naysayers , that it seems ,will say almost anything just for the sake of argument , or just to cloud up a good thread. Anyway, my issue is that , your very knowledgeable and im a newb so a lot of what you post goes over my head. Ive bought a bunch of batteries and would like to put em in a bunch and bulk charge to 4. 15v( ill say) MY QUESTION is, could you (in simple terms for me) tell me exactly what i need to do to mod a 5v meanwell to <4.2v and variable amperage? I don't doubt that you've already gone over this but I just cant seem to pin down exactly what id need to do . help? thnx doug

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Re: Homemade Battery Packs

Post by teslanv » Apr 21, 2014 10:41 am

My 12S9P Pack was a bit lackluster on my 750W bafang. I found a better application for it.

Reconfigured as 6S18P and installed in a stand-up Scooter.

https://endless-sphere.com/forums/viewto ... 12&t=59110
I build custom ebikes.
http://www.westcoastelectrics.com
West Coast Electric Cycles
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DrkAngel
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Re: Homemade Battery Packs

Post by DrkAngel » Apr 21, 2014 11:34 am

douglashart wrote:Drk angel, been following your thread for months now . im very newb, but trying to learn. I find your logic quite sound , despite the naysayers , that it seems ,will say almost anything just for the sake of argument , or just to cloud up a good thread. Anyway, my issue is that , your very knowledgeable and im a newb so a lot of what you post goes over my head. Ive bought a bunch of batteries and would like to put em in a bunch and bulk charge to 4. 15v( ill say) MY QUESTION is, could you (in simple terms for me) tell me exactly what i need to do to mod a 5v meanwell to <4.2v and variable amperage? I don't doubt that you've already gone over this but I just cant seem to pin down exactly what id need to do . help? thnx doug
Look over ES Wiki article - MeanWell S-150-5 1st.
If different model of MeanWell ... PM or post back up.

Quick cheats:
Add 1-2k resister to R33 = regulate Amps (minimal disassembly method - tack new resister legs to top of R33 legs )

1 - Replace SVR1 with 2k pot = lower voltage. or
2. replace R25 with 2k resister = lower voltage (Cut-n-Paste = capable of completing without full disassembly.
Cut legs near resister body
Solder new resister legs to old resister leg remnants.) or
3. add 1k resister in series with R25 = lower voltage
Last edited by DrkAngel on Apr 30, 2014 8:53 am, edited 2 times in total.
A little learning is a dangerous thing;
Drink deep, or taste not the Pierian spring:
There, shallow draughts intoxicate the brain,
And drinking largely, sobers us again.

I enjoy enlightening ... and enlivening the spirit of the innovators.

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Index - Homemade Battery Packs - Updated - November 2015

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douglashart
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Re: Homemade Battery Packs

Post by douglashart » Apr 21, 2014 4:57 pm

THNX DA, I may well have read that but got confused , but you've condensed it to 2 pages that are to the point (of my needs).Ill be digesting this for a few days , then sure ill have questions. thnx again

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Re: Homemade Battery Packs

Post by dnmun » Apr 21, 2014 10:10 pm

DrkAngel wrote:Congratulations Dnmun!

I'm not sure what your original agenda was ... but you have succeeded in making ebeach look like a comparative genius!
At least he now, finally, seems to realize that self discharge is a factor - "small steps".
dnmun wrote: how will you prove your argument that the self discharge rate is the critical parameter to establish cell storage capacity?
1st, ebeach, somehow deluded himself into thinking this same thing, that self discharge was being promoted to determine capacity!
Since then I, and others, have repeatedly, and vehemently!, posted that self discharge has nothing to do with capacity.
You even complained about me shouting this!
Now, ... you, apparently after reading these denials repeated time and time again and again, still seem to have gotten that same delusion stuck in your head!
Do you suffer from that mentally debilitating form of myopia that only lets you see what you want to see?
Has ebeach somehow spawned some form of mental infection? ... mental constipation? ... !!!
Flush that crap out of your head!
It's too full and has covered your eyes!

Oh ... and FYI ... Lithium Iron has not been discussed here ... and is way different than Lithium ion (Cobalt).
you are just a jerk.

where did you prove your point that a cell that self discharges will drain all the other cans in parallel?

where did you decide that some types of cans require a different charging voltage?

how do you come up with these silly ideas and continue to insult other people when they point pout that your techniques are nothing but your own internalized ideas with no basis in fact since none of your presumptions have been demonstrated.

you think that just by insulting other people who try to inject some reality into your own myopic thread that you can somehow be right about something even though there is no evidence that any of this stuff means a thing. all these graphs and charts are totally meaningless.

so instead of proving your point you just insult me and ebeach as though that proves your point but it just proves you are a jerk. demanding that the insiders remove his threads because you don't approve of what he said as though you are god himself.

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Re: Homemade Battery Packs

Post by DrkAngel » Apr 21, 2014 10:29 pm

dnmun
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The intelligent and open minded, invariably, seem to benefit.
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2007blueprius
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Re: Homemade Battery Packs

Post by 2007blueprius » Apr 22, 2014 12:33 am

this may be a bit off topic but not really,

I folowed the thread, but I don't remember seeing any ideas, suggestions as to connectors to be used, I had a power supply that i tinkered with, exposed wires and gator clips, I must have done something to cook it, so I am looking to build one right for a change, and I thought maybe using the anderson plugs commonly found on the popular hobbly king packs may not be sucha a bad idea, but I am not sure which ones to get.

found http://www.mouser.com/Search/ProductDet ... 879-1330G4 I think this will do, says 12 to 16 ga on it, figured I'd order half dozen in black half in red, use some on the power supply, some could be used on the pack?? Thing is I'd like to get the same part comonly used on the HK paks so that at some point they could be compatible, also liked the andersons because they are genderless

12 ga should be good for a 48v pack???? I think that is pretty common, anyway I had been collecting cells and I am about to rig up a new PS, any input would be much apreciated

I just ran a forum search and the PP75 http://www.mouser.com/ProductDetail/And ... oHCIvQo%3d apear to be the upgraded conectors,

also http://hobbyking.com/hobbyking/store/__ ... em_6S.html these were sugested to me on a different project, I figured they could come in handy, keeping packs balanced, a cheap bms solution I guess, supposedly they have a discharge function, so I am thinking they may be usefull monitoring discharge, I am not the wiser, just trying to get a shopping list together, for knicknacks that could be usefull in such builds, so any sugestions much apreciated

George

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Re: Homemade Battery Packs

Post by alsmith » Apr 22, 2014 7:48 am

2007blueprius wrote:this may be a bit off topic but not really,

I folowed the thread, but I don't remember seeing any ideas, suggestions as to connectors to be used, I had a power supply that i tinkered with, exposed wires and gator clips, I must have done something to cook it, so I am looking to build one right for a change, and I thought maybe using the anderson plugs commonly found on the popular hobbly king packs may not be sucha a bad idea, but I am not sure which ones to get.

found http://www.mouser.com/Search/ProductDet ... 879-1330G4 I think this will do, says 12 to 16 ga on it, figured I'd order half dozen in black half in red, use some on the power supply, some could be used on the pack?? Thing is I'd like to get the same part comonly used on the HK paks so that at some point they could be compatible, also liked the andersons because they are genderless

12 ga should be good for a 48v pack???? I think that is pretty common, anyway I had been collecting cells and I am about to rig up a new PS, any input would be much apreciated

I just ran a forum search and the PP75 http://www.mouser.com/ProductDetail/And ... oHCIvQo%3d apear to be the upgraded conectors,

also http://hobbyking.com/hobbyking/store/__ ... em_6S.html these were sugested to me on a different project, I figured they could come in handy, keeping packs balanced, a cheap bms solution I guess, supposedly they have a discharge function, so I am thinking they may be usefull monitoring discharge, I am not the wiser, just trying to get a shopping list together, for knicknacks that could be usefull in such builds, so any sugestions much apreciated

George
What current will it carrying? That's what's needed. There are many web sites with this info in handy table form, and it's been discussed in several threads here on e-s, it's worth checking out by a forum search- you get advice and experience more quickly than waiting or replies, and maybe some things you haven't even thought of!

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Re: Homemade Battery Packs

Post by DrkAngel » Apr 22, 2014 8:44 am

Only because I got started with them, and had good success, I've been recommending Deans - T Plugs.

Typically rated ≥60Amps
Image
Deans Style or Deans Compatible are cheaper and typically of good quality.

Limitation of these style plugs is that you are limited to paired connections.
Unless ... you use both connections as a single connection.

As 120Amp connector, or 60Amp ... with redundant backup!

Update - Converting to XT60 plugs on all applications


Image

For smaller projects I've begun using Mini Deans Plugs

At least 1 source rates at 30Amps
Image

Wire Gauge

I take the UL rating for copper wire of:
14ga = 15A
12ga = 20A
10ga = 30A
8ga = 50A

And double it for eBike application:
14ga for 30A
12ga for 40A
10ga for 60A
8ga for 100A
Attachments
Deans mini.JPG
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A little learning is a dangerous thing;
Drink deep, or taste not the Pierian spring:
There, shallow draughts intoxicate the brain,
And drinking largely, sobers us again.

I enjoy enlightening ... and enlivening the spirit of the innovators.

New & Improved - Acronym Definitions

Index - Homemade Battery Packs - Updated - November 2015

EBike Toolbox - Bargains! $

Endless Sphere Wiki

2007blueprius
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Re: Homemade Battery Packs

Post by 2007blueprius » Apr 22, 2014 12:34 pm

once you find something that works guess you stick with it, kindof why I wanted to start off with something common so at a later date it is compatible with whatever else I may acuire

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Re: Homemade Battery Packs

Post by teslanv » Apr 22, 2014 12:41 pm

2007blueprius wrote:once you find something that works guess you stick with it, kindof why I wanted to start off with something common so at a later date it is compatible with whatever else I may acuire
I really like these. http://www.hobbyking.com/hobbyking/stor ... =4mm%20hxt

Way easier to solder than a Deans T connector, and plug right into LiPo packs.
I build custom ebikes.
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