A123 AMP20M1HD-A Battery pack kit

[bowlofsalad]

Yesterday i finished testing each single A123 cells and began to assemble the kit.

Everything worked fine and i am 100% satisfied with the kit quality.
Except that i feel a bit confused about the "L" shape main contact made of copper and that make direct electrical contact to the aluminum tab of the cell.

There is an important galvanic corrosion potential between aluminum and copper. Maybe not in the next week, but over the years it will get worst and begin to oxidyze.

I am looking for a solution about that.

Doc

I don't know if you found a solution, but you might look into a product called 'ox gard' or noalox. Good keyword: anti-oxidant compound. Whatever the surface may be, if there isn't any chance of water washing away whatever is on the surface or if the area is going to be generally waterproofed, a small amount of oil might do the trick for a long long time, just be sure to cover all of the surface. Perhaps spraying the oil would allow all surfaces to be drenched in oil.

Products like ox gard are extremely viscous, so getting it to any nooks/crannies may be hard to do.

 

[megacycle]

That's an interesting graph.
If a load is drawn could expect the voltage sag to indicate SOC, even though discharge curve is fairly flat at low resolution.
Temperature and test equipment connection method and accuracy would throw it all out though measuring 10's of mV.
Thinking dv/dt measurement might work in any case, like if pulling 10A and starting to fall at 10mV/s trip or alarm.

 

[Harold in CR]

About "Galvanic Corrosion". As a lineman for a New Jersey Power Co. in the 60's, we had a small rubber "pot" that we kept full of No-OX-ID grease, that was smooshed onto the copper and aluminum (NEW PRODUCT) back then, to help with the corrosion. We also had "Burndy Bugs" that were a 3 part clamp, that would physically separate the 2 conductors, while repelling corrosion.

We used a very stiff bristle brush to smoosh the grease on all exposed areas, then clamp, then coat the finished connection, then wrap with "friction tape", that tar covered fabric tape that existed way before vinyl tapes were invented.

After having been in the open air, in a salt fog/stormy environment, for many years, we would open up a connection for changing conductors, and the whole connection was still as shiny and corrosion free as when first done up. The tape was nearly rock hard, but, keeping any moisture out of the connections is key to preventing corrosion.

I used to have a small tin of the stuff, and would clean my battery terminals on all my vehicles, and smear it all with that grease. Didn't take all that much, and batteries would last 6-7 years, or longer, depending on the age of the battery. I always bought used vehicles.

Wish I still had that tin of grease.

I googled no-ox-id, just as it's spelled, and, a company in Chicago Illinois, USA makes or sells it.

 

[Doctorbass]

About "Galvanic Corrosion". As a lineman for a New Jersey Power Co. in the 60's, we had a small rubber "pot" that we kept full of No-OX-ID grease, that was smooshed onto the copper and aluminum (NEW PRODUCT) back then, to help with the corrosion. We also had "Burndy Bugs" that were a 3 part clamp, that would physically separate the 2 conductors, while repelling corrosion.

We used a very stiff bristle brush to smoosh the grease on all exposed areas, then clamp, then coat the finished connection, then wrap with "friction tape", that tar covered fabric tape that existed way before vinyl tapes were invented.

After having been in the open air, in a salt fog/stormy environment, for many years, we would open up a connection for changing conductors, and the whole connection was still as shiny and corrosion free as when first done up. The tape was nearly rock hard, but, keeping any moisture out of the connections is key to preventing corrosion.

I used to have a small tin of the stuff, and would clean my battery terminals on all my vehicles, and smear it all with that grease. Didn't take all that much, and batteries would last 6-7 years, or longer, depending on the age of the battery. I always bought used vehicles.

Wish I still had that tin of grease.

I googled no-ox-id, just as it's spelled, and, a company in Chicago Illinois, USA makes or sells it.

That is great to know that it prevent corrosion, but what about the contact resistance increased by that grease? how does it affect the contact... grease is an insulator i guess?

I wonder if at high current let sau 200A on 2 sq cm surface if it would affect?

Doc

 

[bowlofsalad]

About "Galvanic Corrosion". As a lineman for a New Jersey Power Co. in the 60's, we had a small rubber "pot" that we kept full of No-OX-ID grease, that was smooshed onto the copper and aluminum (NEW PRODUCT) back then, to help with the corrosion. We also had "Burndy Bugs" that were a 3 part clamp, that would physically separate the 2 conductors, while repelling corrosion.

We used a very stiff bristle brush to smoosh the grease on all exposed areas, then clamp, then coat the finished connection, then wrap with "friction tape", that tar covered fabric tape that existed way before vinyl tapes were invented.

After having been in the open air, in a salt fog/stormy environment, for many years, we would open up a connection for changing conductors, and the whole connection was still as shiny and corrosion free as when first done up. The tape was nearly rock hard, but, keeping any moisture out of the connections is key to preventing corrosion.

I used to have a small tin of the stuff, and would clean my battery terminals on all my vehicles, and smear it all with that grease. Didn't take all that much, and batteries would last 6-7 years, or longer, depending on the age of the battery. I always bought used vehicles.

Wish I still had that tin of grease.

I googled no-ox-id, just as it's spelled, and, a company in Chicago Illinois, USA makes or sells it.

That is great to know that it prevent corrosion, but what about the contact resistance increased by that grease? how does it affect the contact... grease is an insulator i guess?

I wonder if at high current let sau 200A on 2 sq cm surface if it would affect?

Doc

I hope this doesn't come out wrong, I don't mean any offense. Galvanic reaction requires an electrolyte. I believe the idea is the product would create a sort of sealed environment around the surfaces. The surfaces are attached and then sealed or coated.

Just to be clear, corrosion doesn't occur just because two different kinds of metals contact each other. If you put the two most far apart or different kinds of metals together, touching, in a sealed environment with an inert gas, they'd likely never corrode.

 

[Bison_69]

Hi DoctorBass,

Here is a stuff Stephane locally available at Crobel called Noco NCP2 CB104 (4 oz.) 13.95/ea
There is a small brush built-in the cap to apply it...
http://www.atbatt.com/images_mlg/cb104.jpg

This is the stuff I am using on my 16 prismatics cells setup.

 

[ambroseliao]

I bought some Ideal Naolox for my future builds. Can't say if it works or not yet!

http://www.idealindustries.com/prodDetail.do?prodId=noalox&div=5&l1=accessories

 

[megacycle]

http://www.alibaba.com/product-gs/407377361/Copper_Aluminum_Bimetal/showimage.html.

Bimetal foil aluminum copper, even as thin as a tab @ 0.2mm.

 

[agniusm]

Posting this to see if there is some interest in complete kits. Again, few changes:
1. Front cover plate will not be included as there will be PP plastic (100C) cover vacuum formed to hide all connections.
2. Only Front blocks used.
3. Brass nuts soldered to the PCB to further ease assembly
4. Complete PP(100C) bottom cover included

Nothing else will be required to assemble your packs, except maybe some kapton tape, some foam.

The price is working out at 101USD for 6S kit. I am thinking making these available:
4S for ICE automotive use
6S for spaced modules
12S
16S
24S
I am not competing with ONS kits nor others. If someone is in Europe i can build required batteries for them for a fee.

 

[Hoghead03]

I'm kind of new to the forum and late to purchase your kits, but by building your own battery pack is the only way you the know the quality. So put me down on your list for 3 6S kits maybe more Glad your thinking about!

 

[joepah]

Posting this to see if there is some interest in complete kits. Again, few changes:
1. Front cover plate will not be included as there will be PP plastic (100C) cover vacuum formed to hide all connections.
2. Only Front blocks used.
3. Brass nuts soldered to the PCB to further ease assembly
4. Complete PP(100C) bottom cover included

Nothing else will be required to assemble your packs, except maybe some kapton tape, some foam.


The price is working out at 101USD for 6S kit. I am thinking making these available:
4S for ICE automotive use
6S for spaced modules
12S
16S
24S
I am not competing with ONS kits nor others. If someone is in Europe i can build required batteries for them for a fee.

I'm looking to buy a 60v ~12 ah pack for my BMC4 motor.... Please PM me with the details.

 

[agniusm]

I'm looking to buy a 60v ~12 ah pack for my BMC4 motor.... Please PM me with the details.

These are 20AH cells non other capacity would be available. Lifepo4 chemistry, so 3.3V nominal for these A123 cells: 4S - 12V, 6S - 20V, 12S - 36V, 16S - 48V, 24S - 72V roughly

 

[chroot]

Look nice case with sealed on top protecting the A123 battery pouch. I like it and when are you start selling 20S and 24S kit?

 

[bowlofsalad]

I imagine there is a reason why you don't make 8s kits, I have no idea what it is. I tried searching for 8s, but it said the term was too common. Apologies if this question has been asked several times. Would 12s be an option instead of 8s?

I am interested in making 8s packs in order to make two 8s packs so I can use a RC balance charger instead of a bulk charger. It seems RC balance chargers don't go up to 16s, bleh.

 

[agniusm]

I imagine there is a reason why you don't make 8s kits, I have no idea what it is. I tried searching for 8s, but it said the term was too common. Apologies if this question has been asked several times. Would 12s be an option instead of 8s?

I am interested in making 8s packs in order to make two 8s packs so I can use a RC balance charger instead of a bulk charger. It seems RC balance chargers don't go up to 16s, bleh.

No problem, i wouldn't like to go through 40+ pages looking for answers myself The reason is simple - cost. Second - little use 24V. I made this kit listening to community's wishes and it will work with your balance charger. There is balance port on the kit for balancing cells but the traces were upgraded to accept up to 7A charge of the battery through this port. Instead of making cable for your BMS, you make harness for your balance charger. Here is my example charging through balance port:

Course you would have to charge it in two stages, first 8 and then another. I am not sure if you can plug in two 8s sections of your 16S pack into those RC charger adapters as it will more likely short.
With these i have, you can make any odd configuration pack. Say you would need 10S, thats 4S+6S;
20S would be 16S+4S kits, 22S - 16S+6S kits etc.

 

[Hoghead03]

Right! That's the beauty of your system very flexible. I changed my mind make it 1-16S, 1-24S.

 

[agniusm]

I've got an interested person for some kits without molded enclosures if someone is interested to jump in that train? Prices are the same as on first page or in for sale section +shipping, mostly 30USD - Canada, US of A, Australia, Europe, couple $ cheaper.

 

[Doctorbass]

I've got an interested person for some kits without molded enclosures if someone is interested to jump in that train? Prices are the same as on first page or in for sale section +shipping, mostly 30USD - Canada, US of A, Australia, Europe, couple $ cheaper.

I might be interested by another 16s kit and a 6s kit. will depend if i can get the great 20Ah pouch again from victpower.

But i would really be interested also to have some 2p kit!!

Doc

 

[gua_rana]

to gua rana
your volts/dod graph is very interesting, is the curve traced a line of best fit predicted by computer? is there a formula predicted also.
There is definitely a pattern there good enough to predict capacity remaining. It looks like a parabolic curve. Below 40% theres not much data
around that area so hard to say much there, but after 60% dod the data looks very predictable.

It is a third order curve fit. Here's the data so you can make whatever you want with it.

 

[agniusm]

Making order for pcb's On Monday, if some one wants to order, make a deposit to agniusmk@gmail.com of 40USD thru paypal. State the kit/kit's you are ordering on PayPal notes to seller. Deadline Monday, 9AM GMT+2. Thank you.

 

[whatever]

thanks gua rana data is useful

 

[agniusm]

i was wandering about in Alibaba, emailing manufacturers for quote for brass square nut. One came back to me with the price of 80US cents for one M3 nut. How is that for cheap Chinese stuff. And they specialize in making such fixings, not like asked for custom. Perhaps they went mad with pricing for the stuff for everything.

 

[agniusm]

I have 10 6S sets from first run for reduced price of 30$ each. There is no threaded blocks included. It's up to you to make them or just use 3mm nut and solder it to PCB like so:

here is the content included:

Zoomed In:

Combined shipping applied.

EDIT: x 6 left

 

[agniusm]

Started prototyping fully enclosed battery pack. The board is 10mm on each edge wider to sandwich box-pcb with cells-top cover together:

Will try to use 8mm bullets soldered to copper terminal and 4mm bullets for charging.

 

[100volts+]

subscribed