Search found 1436 matches

by deVries
Aug 27 2013 9:01pm
Forum: Battery Technology
Topic: A123 20AHr Pouch Cell Battery Build & Info Thread
Replies: 985
Views: 143787

Re: A123 20AHr Pouch Cell Battery Build & Info Thread

oatnet asks: Devries where did you end up buying your a123 20ah pouch cells from? Sorry to say I never got any, ever, though I would like to get 32 confirmed good cells for Rachel's two trikes. (She is disabled, and I'm trying to help her w/battery, etc.) I am seeing all sorts of advice, input and ...
by deVries
Aug 27 2013 10:42am
Forum: Battery Technology
Topic: Samsung INR18650-20R .. yes these cells can punch, new 24R
Replies: 206
Views: 46605

Re: Samsung INR18650-20R .. yes these cells can punch

I think that Sony cell is neat BUT they are expensive compared to the 20r. Also I can't find a discharge graph for it but supposedly it can do 50 amps discharge. On their last shipment they included one of the sony cells for me to test. We'll see how they perform but the price is a bit steep. Has a...
by deVries
Aug 26 2013 7:25pm
Forum: Battery Technology
Topic: Creating my own battery pack
Replies: 38
Views: 3011

Re: Creating my own battery pack

Ok I see. I found the answer: Solder has a resistivity of about 0.00000016 ohms per inch, so if conductive glue is around 30 ohms per inch then it's about 187,500,000 times poorer as a conductor than solder. Jeremy http://www.endless-sphere.com/forums/viewtopic.php?f=2&t=9395 So no conductive epoxy...
by deVries
Aug 26 2013 5:11pm
Forum: Battery Technology
Topic: Creating my own battery pack
Replies: 38
Views: 3011

Re: Creating my own battery pack

So you'll loose 5kg (11 lbs). I understand in your calculation that its significant weight loss for you. If I were to also want weight loss, I'd first aim to take it out of my fat ass! Seeing as hows I built an ebike to move that ass around to begin with, it kinda defeat the whole purpose! :oops: I...
by deVries
Aug 25 2013 7:16pm
Forum: Battery Technology
Topic: Arkmundi's saga making & maintaining an A123 AMP20 battery
Replies: 149
Views: 19834

Re:

Are you crazy? I am using the voltphreaks single chargers (16S)' and these single chargers still running solid. It always be exact 3.65V on my fiancee lifep04 pack much better than letting the BMS controlled because the BMS always shoot high as much exceed 3.9V. I was afraid that might shorten life...
by deVries
Aug 25 2013 11:51am
Forum: Battery Technology
Topic: Dr.Bass Steveo found 7s3p Module! Awesome Price!!
Replies: 592
Views: 82543

Re: Dr.Bass Steveo found 7s3p Module! Awesome Price!!

that is very affordable for some of my projects so put me down for 1. when and where do we pay? pm sent in case you dont read the forums This is an old thread. See OP. But, maybe someone will sell you their used ones they shipped to the USA??? :) Also, we need feedback about these modules. I wish p...
by deVries
Aug 25 2013 8:46am
Forum: Battery Technology
Topic: A123 20AHr Pouch Cell Battery Build & Info Thread
Replies: 985
Views: 143787

Re: A123 20AHr Pouch Cell Battery Build & Info Thread

Devries where did you end up buying your a123 20ah pouch cells from? Sorry to say I never got any, ever, though I would like to get 32 confirmed good cells for Rachel's two trikes. (She is disabled, and I'm trying to help her w/battery, etc.) I would suggest to continue to follow Doctorbass and his...
by deVries
Aug 25 2013 2:16am
Forum: Battery Technology
Topic: A123 20AHr Pouch Cell Battery Build & Info Thread
Replies: 985
Views: 143787

Re: A123 20AHr Pouch Cell Battery Build & Info Thread

oatnet wrote:Devries where did you end up buying your a123 20ah pouch cells from?
Sorry to say I never got any, ever, though I would like to get 32 confirmed good cells for Rachel's two trikes. (She is disabled, and I'm trying to help her w/battery, etc.)
by deVries
Aug 24 2013 2:49pm
Forum: Battery Technology
Topic: A123 Cells, new, legit, factory direct!
Replies: 52
Views: 8851

Re: A123 AMP20 Cells, new, legit, factory direct!

Bottom Line: $70 per cell plus shipping is still too expensive. Also, these need to be verified manufactured in 2013. A123 may have a large surplus of 2012 cells, which I would never buy near that price.
by deVries
Aug 24 2013 1:07pm
Forum: Battery Technology
Topic: A123 20AHr Pouch Cell Battery Build & Info Thread
Replies: 985
Views: 143787

Re: A123 20AHr Pouch Cell Battery Build & Info Thread

What voltage and Ah battery are you planning on building? For what application? electric bike 48v 20Ah I would suggest to continue to follow Doctorbass and his method to package these cells. Your ebike application is not putting much demand on these cells vs their intended car applications usage. D...
by deVries
Aug 24 2013 7:58am
Forum: Battery Technology
Topic: A123 20AHr Pouch Cell Battery Build & Info Thread
Replies: 985
Views: 143787

Re: A123 20AHr Pouch Cell Battery Build & Info Thread

WB9K, is there a way to "decode" the manufacturing date by the markings printed on these cells? Anyone know how to do this?

Thanks.
by deVries
Aug 23 2013 11:55pm
Forum: Battery Technology
Topic: A123 20AHr Pouch Cell Battery Build & Info Thread
Replies: 985
Views: 143787

Re: A123 20AHr Pouch Cell Battery Build & Info Thread

ejonesss wrote:i have seen pressurized boxes on the telephone poles that have a warning saying to remove the screws in a certain order to release the pressure safely.
What voltage and Ah battery are you planning on building? For what application?

Thanks.
by deVries
Aug 23 2013 9:20am
Forum: General Discussion
Topic: RESOLVED! ES member fell very ill & is working this out :)
Replies: 42
Views: 4918

Re: RESOLVED!!! Fellow ES member fell very ill & unable to c

Yes, it should be deleted. Too much false suspicion and conjecture against an innocent individual. Thanks Hillhater for stepping up to say this. I appreciate it very much... I am just another ES reader here. If you feel that this thread provides too much false suspicion and conjecture against you, ...
by deVries
Aug 22 2013 7:55pm
Forum: General Discussion
Topic: RESOLVED! ES member fell very ill & is working this out :)
Replies: 42
Views: 4918

Re: RESOLVED!!! Fellow ES member fell very ill & unable to c

Yes, it should be deleted. Too much false suspicion and conjecture against an innocent individual. Thanks Hillhater for stepping up to say this. I appreciate it very much... FYI read this: Rachel Resolution... Done. Sent: Thu Aug 22, 2013 9:19 am From: deVries To: Ypedal bigmoose lifereinspired Hi ...
by deVries
Aug 21 2013 7:49pm
Forum: Battery Technology
Topic: Dr.Bass Steveo found 7s3p Module! Awesome Price!!
Replies: 592
Views: 82543

Re: Group Buy? Dr.Bass Steveo found 7s3p Module! Awesome Pri

Thought I would bump this thread to ask all the buyers of the modules how these have worked out?

Did you have much of a failure rate?

Did you find a way to do repairs?

How did these modules work out for your project?

What was your module application for?

Thanks. :D
by deVries
Aug 21 2013 1:12pm
Forum: Battery Technology
Topic: A123 20AHr Pouch Cell Battery Build & Info Thread
Replies: 985
Views: 143787

Re: A123 20AHr Pouch Cell Battery Build & Info Thread

i think it has to do with the over all mass, an EV sized pack is heavy and requires significant measures to keep it from shaking itself to bits ( if the cells move , at all, in relation to each other, the tabs would break obviously ) , a 15 lbs ebike pack on the other hand, can be strapped down sol...
by deVries
Aug 21 2013 12:40am
Forum: Battery Technology
Topic: A123 20AHr Pouch Cell Battery Build & Info Thread
Replies: 985
Views: 143787

Re: A123 20AHr Pouch Cell Battery Build & Info Thread

deVries, I believe that wb9k already explained it's to keep the electrolyte evenly dispersed across the electrode, and prevent hot spots on the cells. Long term, that increases IR. Correct, but the point I was making too is how does this PSI rating relate to a static environment vs the hostile vibr...
by deVries
Aug 20 2013 1:19pm
Forum: Battery Technology
Topic: One KiloWatt 18S Bulk Charger
Replies: 170
Views: 20106

Re: One KiloWatt 18S Bulk Charger

Hi Alan, thought I'd bump this tread to see if you made any further progress or found a different solution??? I think you were planning to dev some add-on for these.

Thanks.
by deVries
Aug 20 2013 8:37am
Forum: Battery Technology
Topic: A123 20AHr Pouch Cell Battery Build & Info Thread
Replies: 985
Views: 143787

Re: A123 20AHr Pouch Cell Battery Build & Info Thread

[...] Lab testing....yes, lots of it, but it can only tell you so much so fast. That, and the data is proprietary so, sorry, I can't just reach into the server and post specs or test data here. Honestly I would be surprised if such testing had been done in a way that would be directly applicable to...
by deVries
Aug 20 2013 5:14am
Forum: Items for Sale - New
Topic: Assembled Hi-Power LiPo battery packs - any interest?
Replies: 574
Views: 121715

Re: Assembled Hi-Power LiPo battery packs - any interest?

Hi Chris,

I'm guessing you would recommend the 40c 5000mAh over the 25c 5800mAh because of the higher C rating which possibly indicates better quality too? Less rejects and/or longer lifespan/cycles? Any differences you've noticed?

Thanks.
by deVries
Aug 19 2013 11:08pm
Forum: E-Bike General Discussion
Topic: Anyone charging there battery in cold room?
Replies: 9
Views: 955

Re: Anyone charging there battery in cold room?

I am planning on charging my limn battery in the garage which can get a bit below freezing. I definitely would not recommend charging anywhere near freezing or below. Either create a warm area with a space heater or bring the battery inside house or warm area to charge or warm-up before charging. 5...
by deVries
Aug 19 2013 10:05pm
Forum: Battery Technology
Topic: A123 20AHr Pouch Cell Battery Build & Info Thread
Replies: 985
Views: 143787

Re: A123 20AHr Pouch Cell Battery Build & Info Thread

Has anyone come-up with some good pressurization ideas to compress these light weight wise??? Also, can the wb9k A123 guy or someone with the Specs tell us what the minimum psi we might use instead of the maximum? Also, going with the minimum psi vs max is there any data about how much less lifespan...
by deVries
Aug 24 2012 5:31am
Forum: Battery Technology
Topic: Petition A123 Systems for factory access
Replies: 15
Views: 1937

Re: Petition A123 Systems for factory access

Do NOT invest in A123 at this time. This company is headed for "takeover restructure" by total stock dilution of current common shares making your investment worthless or a far less tiny fraction than what you paid. OR, more likely, this company will go into receivership and all current common share...
by deVries
Aug 24 2012 5:13am
Forum: Battery Technology
Topic: 600W 10-60V to 12-80V converter
Replies: 81
Views: 7081

Re: 600W 10-60V to 12-80V converter

I have this cheap 600W 24V power supply (http://www.hawk-rc.net/index.php?route= ... uct_id=255) for my hyperion. This PS is overkill, and it is NOT STRESSING this PS to power your Step-Up Converters. It can easily power one or more than one converter without overloading this power supply. When you...
by deVries
Aug 24 2012 4:26am
Forum: Battery Technology
Topic: 600W 10-60V to 12-80V converter
Replies: 81
Views: 7081

Re: 600W 10-60V to 12-80V converter

I tried on another one and was able to pull 15A input... but it only has an output of 110W max. Was this with 2 in parallel??? but according to Zomtek it's because my power supply is unstable. Also, why aren't you trying to use your 24v MW PS ??? Is the noise coming from your Step-up converters or ...