show my new li-polymer battery pack!!!!

fechter

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Excellent!

How much does it weigh?

Can you post a larger size pic of the BMS circuit (like so I can read the part numbers)? I don't really want to copy it, I just want to know how it works.

I'd sure like one of those babys. Bet I couldn't afford it though :cry:

What does the BMS do when the current tries to go over 100 amps?
 
The BMS looks good- even if the picture is a bit fuzzy.
Does it transfer charge between cells or just monitor during discharge?
I see the bank of resistors to dissipate excess charge, and the big FETs to limit the current, but I'm trying to figure out the pairs of surface mounted small FETs.
 
Is this the same 48v 20ah lithium pack Knoxie's written about?
http://endless-sphere.com/forums/viewtopic.php?t=115&highlight=20ah
 
aiicsu said:
fechter said:
OK, then it's down to price.
How much $$ for one?
Is there a matchin charger?
yes!!there is a matching charger.
the charger is 58.8V/4A
the price is USD 70/pcs
Is that price right? $70.00 ?

If they are $70.00 each, I would like to order 100 of them please :wink:
 
aiicsu said:
I am sorry,you mistake what I say .the charger's price is $70.00/pcs
the battery pack is about $630.00/set
Still not a bad price, I might take you up on that offer in the near future.
 
aiicsu said:
48V/20Ah(14s)
dimension:160*170*270mm
voltage:58.8~42V
Capacity:20Ah
max current:100A
the pack is about 8KG.
the battery pack is about $630.00/set
the charger is 58.8V/4A
the charger's price is $70.00/pcs

Hello aiicsu,

We like the high power and low weight of your new Li-Polymer batteries very much! Thank you for showing them to us.

I have a few questions.
Does your BMS have over-charge and over-discharge protection?

would it damage the batteries or BMS circuits if two or more of these packs were wired in series?

You sell each battery/charger kit for $700.00. That is a good price, but alot of money to spend. Would you like to offer discounts for 5 or more battery/charger kits to members of Endless Sphere if we buy them all at once?

Where do you make these in China?


Thanks again,

-Stevil
 
Those batteries are really tempting. I have a 2006 Emax so if I were to purchase 2 of these batteries and put them in parallel:

1. Stock Emax has either 36AH or 40AH Silicone SLA's. In reality with the Peukert effect, I am guessing about 27AH-30AH ?? So with these 2 20AH lithium packs I am guessing more range and better performance ??

2. Stock Emax has 8 batteries that weight about 15 pounds each for a total of approx. 120 pounds. 2 of these Lithium packs are about 35 pounds for a saving of about 85 pounds :eek:

3. The price of $700 a pack or $1400 for 2, is not that bad compared to some of the other places.



Very tempting, maybe by summer time :) God Bless :)
 
It sounds like they would be great in an Emax. Losing 85 lbs of lead weights will help performance too. I can't remember how much current the Emax runs maximum, but if you use two of these, it should be no problem.

If you're a commuter and use the scooter a lot, the economics of the Li batteries are attractive over the life of the batteries (in theory).

I just wish the price would come down more.
 
It's a great price compared against the rate I just paid to BatterySpace for
this pack

On the other hand, what do we know of your pack?
It is liable to be very good! Yet, if it has a problem,
who can service the pack? What brand are the cells?
Are there any data sheets on the cells?

What is the discharge characteristic?
What is the fire safety rating?
Can the BMS fail in any way which might provoke a venting of the pack?


--These are rhetorical questions.

The price is RIGHT. Who feels like , taking a test ride of the battery pack?


I'm doing it more expensively---willingly, because at least the support firm is here in the USA.


It is a tough question for both seller and buyer--what to do?
You can only do what you have done: make an offer.
Better documentation will inspire more buyers.
Warranty---can you offer any warranty? And how will it be supported?


Thanks for your being here. China is far, far away from most of us.
Yet we live with Chinese goods. We live on Chinese goods.

:D We are totally pwned

and you guys in China know it!

:p
 
fechter said:
If you're a commuter and use the scooter a lot, the economics of the Li batteries are attractive over the life of the batteries (in theory).

Raises an interesting question. As I understand it, Li batteries have an aproximately 4 year shelf life, that is, they're stuffed after that time whether you've used them or not (hence why Thundersky makes the batteries on demand). This is just my understanding, please correct my if I'm wrong.

Either way, my EVT's 50Ah worth of lead is sulphated pretty bad, I can no longer comfortably complete the round trip from home to work (12.5km). I figure I can replace them with Hawker Optima something or others (orange tops) for about $300AU a pop or about $1200 total. For comparison, a while back I priced some Thundersky Li-ions capable of 100A discharge and 50Ah capacity. I think it was about $1600US, can't remember if this included chargers or not.

When the lithiums are gone, they're gone. But the lead, which I believe to be sulphated, should be able to be recovered. I'm building 4 of these: http://members.shaw.ca/pferlow/desulfator.htm (simple version) which by all reports can recover most lead acid batteries to 100% capacity in 0.5 to 1 day per pound of battery. So I should be looking at 2 weeks to 1 month out of action (each Long 50Ah battery weighs 33 pounds), but if it saves me $1200 (and I can just repeat the process each time it happens) then it's well worth it.
 
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