found new cheap site for BMS, LiFePO4 & charger up to 18000W

[Gregory]

Both evpst and ecitypower websites have identical descriptions and pictures of the manufacturing process....one has plagiarised the other, and the ecitypower domain has been registered longer so ....

Allan.z, I think you need to be clear on your intentions and affiliations, people here won't like being toyed with.

 

[caleb7777]

I used paypal with ecity

 

[pwbset]

I used paypal with ecity

I used paypal also. Immediately got asked what voltages I wanted the chargers set to, did I want DC leads, what was my AC source, confirmation of shipping address etc. etc. I've got nothing but great things to say about Jack and company so far. Excellent communication. If the chargers work as specified I'll likely order more stuff from ecity in the future. I could care less whether someone has a manufacturing plant or not if the products are affordable and work and the customer service is good I'm sold. Getting tired of these Vendor Warsâ„¢. :lol:

 

[michaelplogue]

I doubt that EITHER company actually has a factory - seeing as they are practically next-door neighbors. As pwbset said - I could care less. eCity states that they can provide custom BMSs for however many cells and amps you'd like - which no other company has provided. Whether they do this from a giant clean-room with dozens of lab-coated techs, or the back room of a smokey apartment done by three pimple-faced teenage boys with risque manga posters on the wall - as long as they can produce what they advertise, it's all good.

It seems - from the few items purchased by ES members so far - that they appear to be on the right track. Time will tell if they can keep it up and become a reliable source for us battery addicts across the puddle.

 

[Spasticteapot]

VERY interested. This would cut the cost of my bike project nearly in half.

What discharge rates are these packs rated for?

 

[shinyballs]

nice feedback guys...

How's there bms working so far when charging at high currents(>=1C). Is it "leave & forget", same as the "Even Newer" bms which prevents each cell from overvoltage?

 

[julesa]

I ordered two 400W chargers and two 16s resistor bleed BMSs from Jack at ecitypower.com today, paid via paypal. Very professional, good communication and fast responses, as others said earlier. So far I'm impressed!

 

[boostjuice]

Hi Guys,
evpst have been in this LiFePo4 battery line for about 10years.
aLLAN.Z

I dont think any chinese vendors were selling LiFePO4 battery packs in 1999.........

 

[Gow864]

Hey isn't allan.zz's last post spam? What are the rules here??

 

[michaelplogue]

That clinches it - vendor wars. Disregard anything Allen has stated about eCity - obviously biased.

Allen - piss off and quit this crap. Sell your stuff as you wish, but this sort of competition-bashing crap is childish and unwanted here.

. :x

 

[Doctorbass]

<spam - post deleted>

Allan, i just want to clarify something IMPORTANT HERE.

I discussed with tom and Jack on skype many hours and I asked to know if the CE is a true CE european approaval logo.


and... prepare to fall off your chair guys:

in chineese, CE logo mean Chineese Export !! .. so there is nothing to have with the strict and respected CE approaval regarding quality, specs and safety qualification.

Do your search on wikipedia you will see!

I asked and they admit that it was Chineese Export signification... :?

I like compagny that are fair and straight with us and that dont try things like that with us

I thought is was important to clarify !

Doc

 

[GGoodrum]

i am so disappointed and sad about your bias and bind faith .... you guys....
I have thought you should be openness and Being Realistic.
BUT the facts is not so optimize

If you want to post ads, you may do so in the For Sale section, but we will not tolerate flame wars here between vendors.

-- Gary

 

[caleb7777]

Back to the point of this thread

I have ordered a battery from jack and will up all the pics I can when I get it. Now I really no nothing about how to test these batteries to see how good they are.
So my question is when i get the batt what do you want me to post? multimeter readings, etc

What should i check on when it gets here?
I am sure you guys know what to look for.

I got 48v 15Ah batt with 3C discharge (45A-75A BMS) 45A continuous was the claim

 

[michaelplogue]

Allen -

It's not about blind faith. It's about a history of competing vendors bashing one another here on Endless-Sphere. You are clearly employed by EVPST - as you have once again demonstrated via the thread below (note the source of the charts). You clearly cannot be trusted to be able to provide an unbiased view of one of your competitors. You are not fooling anybody.......

http://www.endless-sphere.com/forums/viewtopic.php?f=14&t=9822

As for spamming: The original poster was done not by someone from eCity, but by a long-time member of this board who was posting the links and information from this company as an alternative source of batteries, chargers and BMSs - not as an advertisement for the company. You - as a representative of a competing company - have come on here slinging mud (despite your claims of not bad-mouthing anybody), and have posted advertisements for your own product.

Make your own thread in the advertisement section of this forum if you want to plug your own products.

.

 

[dnmun]

what to check? ideally measure each cell before it is charged the first time. then monitor how they end up balancing the first time. since they all were manufactured together, any manufacturing variation may show up in that initial self discharge cycle. i guess they test them for continuity in the production line, but the sampling time is likely constant so all that should be normalized.

make sure the charger puts out 59-61V.

i would recommend endplates and pressure straps for the prismatics too. to prevent the swelling, stiff plates relatively, maybe even shorter than full cell height but in the center of the area where the electrodes are coiled.

this could be stuff building up on the separator too, moisture contamination during assembly but seems like real engineered packs like the toyota packs use end plates, honda used cylindricals, metal sleeves. thundersky does too.

don't overtorque the studs, aluminum fatigues under repeated stress.

go easy on the initial charge cycles, bob mcree is quoted at 50 cycles, nobody can be gentle that long, but it may be best to always run in the top of the discharge voltage, not the bottom, the 2k cycle numbers are always using 70% DOD. yada yada.

 

[Gow864]

ecity battery feedback SOON please. I'm waiting for some results before I buy from them.

Cheers,
Gow.

 

[recumbent]

I am still looking for an infineon controller, does keywin still sell them here? Or should i just get one off ebay? there is a seller there selling them called comcycleusa or something

Anyone know if they are legit?

I've ordered and received a 48V Infineon controler from "comcycleusa" and all is good, the controler has a direct connect for the Cycle Analyst also.

 

[caleb7777]

I won't lie dnmun.
You lost lost me at hello

I am assuming that this pack is built when I get it and I don't want to disassemble it

Those tests seem beyond me
if they are simple someone please explain?

 

[caleb7777]

I am still looking for an infineon controller, does keywin still sell them here? Or should i just get one off ebay? there is a seller there selling them called comcycleusa or something

Anyone know if they are legit?

I've ordered and received a 48V Infineon controler from "comcycleusa" and all is good, the controler has a direct connect for the Cycle Analyst also.

Thank you, I ended up ordering from them directly here: http://www.comcycle-usa.com
I could be wrong but I think their ebay prices for the same controller were lower however
Whatever, they got my money I don't worry too much about 10 or 20, after all I already got a good 2000 sunk into my new bike build and have yet to see any of it on my door step

 

[dnmun]

caleb, no problem. the battery is made of a series of individual cells. when they arrive from the factory, they will be partially self discharged from the initial manufacture. before charging the first time, if you measure each cell and record the voltage, that will tell you if any cell is self discharging or 'leaking down internally' faster than the others, so it would have a lower voltage when you measure it. it will also take longer to charge up so when the other cells climb rapidly to 3.7V the cells which had discharged more charge will take longer to fill up and the voltage climb.

so if you do that before the first charge, you know which cell to watch from the start, and can concentrate on preventing it from ever getting too low.

if you look at markcycle's evmotorcycle build, you will see the large plates strapped on the outside of the thundersky prismatic cells he uses. those end plates prevent the cell from swelling during use, and i think swelling is correlated with voids inside the cell which are part of the failure mechanism. so i think it will help the prismatics to last longer if they are clamped in between end plates, like mark has on his.

i am suspecting that the swelling is because stuff clogs up the pores in the separator, and that causes voids to form in the electrolyte/anode or cathode, contact. and early failure. so try to stop it with the clamps so the voids don't form. just my idea.

many people think it is best to restrict the initial charge/discharge cycles to minimum amounts.

don't charge it up and immediately go ride as far as possible until it dies.

go through a number of discharge cycles of only 20-40% at most, then after a few dozen push the limits higher, but i would recommend keeping it as highly charged as possible, for the entire life of the battery.

avoid running down to low voltage cutoff, charge in advance, and as often as possible. make sure your charger does charge the cells all the way up to the 3.65-3.7V level. all imho.

 

[caleb7777]

Sounds good dnmun

If it isn't too hard i will post everything, Jack hasn't shipped yet, he just today asked me for an address. So sadly this will be a while, probably be the last bike part i get
I will have to wait longer to ride..........

 

[dnmun]

no problem, they look a lot like the foxpower cells that duane had. he got a buncha poor cells the second time he ordered, so checking the cells when they come is a good idea, in case they argue with you later about warranty and maybe save you expense of having to ship it back if you have public record too.

 

[pwbset]

Got my two chargers today. 1 week shipping from China to US. Not bad. They came with three prong DC connectors. So here's a couple dumb questions...

1. I can safely ignore the middle prong/ground when hooking this up to Andersons yes?

2. When you check voltages from a charger with a multimeter you don't want a negative reading do you? Here's the deal with the charger that's supposed to be 58.8v output for a 14s LiMn string. The three prong DC connector is labeled with a 'N' and 'L' and a ground symbol. When I hook up my multimeter red to 'L' ('lead' I assumed) and black to 'N' ('negative' I assumed) I get a negative voltage reading of -58.7v which is the voltage I want, but negatively reading. When I hook up the multimeter red to 'N' and the black to 'L' I get a positive voltage reading of 59.2v, which is too hot for my konions by about .22v/cell.. not terrible, but not good either.

So now I'm second guessing myself that because it's power coming "out" of a charger maybe the voltage reading should be negative??? That can't possibly be can it?? Don't know enough about this. The 75v charger is bang on 75v hooked up either way.

I can take macro photos of what's happening if that would help. Here's the charger.. they both look the same.

 

[boostjuice]

Being it's an IEC AC mains plug that is being used for the DC output, the L stands for 'Live' (Often A for 'Active') and the N stands for 'Neutral'. These are standard acronyms for AC mains electrical wiring. Only non double insulated, earthed chassis need a ground connection so you should find that the ground wire is either earthed to the chassis or unconnected. Either way dont connect it to your battery if you get a voltage across the other two wires. It doesnt matter what the polarity the L wire is as you are going to chop off the plug and replace it with andersons, but its a good thing you tested the polarity before commiting your color coded plugs to the wires.
Putting an AC mains plug on the output of a DC charger is a cheap cost cutting measure that is downright dangerous. Someone less educated could easily plug the output of the charger into mains and destroy the charger and/or themselves. The reason chinese vendors do this sort of thing is because AC mains plugs cost a fraction of less common DC plugs due the economies of scale when it comes to producing Mains operated electrial appliances, which all need an AC plug.

This cheap and nasty manufacturing tactic reflects the price you paid for the things.

Got my two chargers today. 1 week shipping from China to US. Not bad. They came with three prong DC connectors. So here's a couple dumb questions...

1. I can safely ignore the middle prong/ground when hooking this up to Andersons yes?

2. When you check voltages from a charger with a multimeter you don't want a negative reading do you? Here's the deal with the charger that's supposed to be 58.8v output for a 14s LiMn string. The three prong DC connector is labeled with a 'N' and 'L' and a ground symbol. When I hook up my multimeter red to 'L' ('lead' I assumed) and black to 'N' ('negative' I assumed) I get a negative voltage reading of -58.7v which is the voltage I want, but negatively reading. When I hook up the multimeter red to 'N' and the black to 'L' I get a positive voltage reading of 59.2v, which is too hot for my konions by about .22v/cell.. not terrible, but not good either.

So now I'm second guessing myself that because it's power coming "out" of a charger maybe the voltage reading should be negative??? That can't possibly be can it?? Don't know enough about this. The 75v charger is bang on 75v hooked up either way.

I can take macro photos of what's happening if that would help. Here's the charger.. they both look the same.

 

[pwbset]

It doesnt matter what the polarity the L wire is as you are going to chop off the plug and replace it with andersons

Thanks for the info boost. Didn't even occur to me to just put Andersons on the straight lead out of the charger... was thinking of keeping those plugs for some reason and putting Andersons on the other side, but what's the point. Doh. Not the brightest bulb in the bunch.