This is directly from Fernando.
Spec Sheet: -Click Here-
Large pic of batteries: -Click Here-
They are indeed 12v 35 ah. I'm very pleased with the fact that they went through the trouble to produce a spec sheet on the batteries. Obviously EVT most likely doesn't manufacturer the batteries, but at least they are providing adequate information.
Waiting to hear back if the bike has battery balancers.
Yes, I agree - big kudos to EVT for making this sort of information available. I hope that we can use that PDF as a template to gather the same information for other batteries. This would then give us a good basis for comparison.
Now, if they'd just pony up and buy the PDF software instead of using the "for evaluation only" version...
John H.
Blue XM-2000
Ann Arbor, MI
http://www.revevllc.com
John H. Founder of Current Motor Company - opinions on this site belong to me; not to my employer
Remember: " 'lectric for local. diesel for distance" - JTH, Amp Bros || "No Gas.
`:?
Thanks Andrew, I'm back to my computer now, and will post everything Fernando has sent me ASAP.
Peace Out,![](http://tinyurl.com/ysafbn)
Gman
What is your vision for the future our growing community?
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Gman
Hi guys,
I wonder why Z20 using smaller batteries?
This is an oem model that using in my EVT-4000e. I found the origional maker, KLB, a TW listed company, big on UPS, and motor battery fields. You may check the spec: http://www.klb.com.tw/dbf/WP50-12NE.pdf
I'm aware of that EVT is different company from EVTAmerica. EVTAmerica is selling EVT's(a TW based company) products, but also import and resale other e-scooters to the States from China.
Jay, Taipei
Jay,
Yes,EVT didn't import from Taiwan any more.I think their 35AH(20hr) battery is too small capacity to bear big current from controller.
Taiwan EVT use 50AH big batteries,still difficulty to bear big current.
I know nothing about the technical side of EVs. It seems like people are saying that the batteries for the Z-20 aren't so great and you're likely going to have a very short range at high speeds. My question is, is it possible to replace the batteries and put a different kind in there, something more high end?
Thanks,
Christopher
Don Cristobal
EVTA Z-20b
---
Ohm is where the heart is.
Hi Christopher,
Yes you will be able to replace the batteries - but the question is with what?
Your best (not accounting for cost) battery choice will be LiFePO4s (these are the best/safest/latest form of Lithium batteries and don't have the thermal runaway (exploding) problems with the Li-Ion cells that made the news a while back).
usatracy is figuring out how to get a good deal on a 60V 10Ah pack and/or a 60V 20Ah pack as a replacement for the XM2000. This will most likely fit in the Z20 - however because most folks haven't seen a Z-20 we don't know for sure if they will fit yet. The Lithium based packs won't suffer from worse performance at high speed because they are more capable of handling sustained large current draws. Also, a 10Ah Lithium pack is apparently about as capable as a 20Ah to 30Ah lead acid pack. It might be that a 10Ah pack is as good as the supplied Z-20 pack - or you might need a 20Ah pack. Time will tell - when folks start riding their Z-20s.
I'm hoping that usatracy's batteries will come in less than $1000 for a 60V 10Ah pack and less than $1500 for a 60V 20Ah pack. But that's just speculation. Keep an eye on this post: http://visforvoltage.org/forum/batteries-and-chargers/1770 And when you hear usatracy cry "Eureka! I've solved it" send him a PM and ask about the possibilities of a Z-20 compatible pack.
Hope this helps.
John H.
Blue XM-2000
Ann Arbor, MI
http://www.revevllc.com - Authorized X-Treme dealer
John H. Founder of Current Motor Company - opinions on this site belong to me; not to my employer
Remember: " 'lectric for local. diesel for distance" - JTH, Amp Bros || "No Gas.
Thanks for the info. Is there a notion as to how much this could potentially improve range and performance?
If you already answered this in your previous reply I apologize, but when I say I have no technical knowledge I really mean it. I do understand that 20Ah pack is twice as big as a 10Ah pack, but truly I don't even know what an "Ah" is other than a mild exclamation.
Thanks,
Christopher
Don Cristobal
EVTA Z-20b
---
Ohm is where the heart is.
`DonCristobal ,
Welcome to the V is for Voltage Community, the best person probably to answer that question is Fernando Pruna, President of EVT America.
Since this is a new thread, I don't know if he's monitoring it or not. I can drop him a email or you can info [at] evtamerica.com and I'm sure he will personally answer your question ASAP.
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Gman
What is your vision for the future our growing community?
Peace Out, <img src="http://tinyurl.com/ysafbn">
Gman
Hi Christopher,
Even when I try and write clearly I end up throwing about acronyms and terms too much :-)
Ah = Amp Hours = the amount of charge a battery holds. So in theory a 20Ah battery holds twice as much energy as a 10Ah one. And, in theory, the 20Ah battery should take you twice as far. With me so far?
Well, unfortunately it's not as straightforward as that! One has to take into account both the chemistry of the battery (is it lead acid or is it lithium?) and the discharge rate (how much power are we asking the battery to deliver).
Until we have some real world data on the Z-20 that's readily available it's going to be really hard to come up with meaningful figures. I believe we can say with high confidence that LiFePO4 batteries will be significantly better than the stock lead acid batteries - and they will also cost you more. I don't know what plans EVT of America have for supplying a LiFePO4 battery for their bike (and that's why I still suggest you keep an eye on the post I mentioned above).
John H.
Blue XM-2000
Ann Arbor, MI
http://www.revevllc.com - Authorized X-Treme dealer
John H. Founder of Current Motor Company - opinions on this site belong to me; not to my employer
Remember: " 'lectric for local. diesel for distance" - JTH, Amp Bros || "No Gas.
`DonCristobal,
You question has been sent to Fernando.
Peace Out,![](http://tinyurl.com/ysafbn)
Gman
What is your vision for the future our growing community?
Peace Out, <img src="http://tinyurl.com/ysafbn">
Gman
`
Peace Out,![](http://tinyurl.com/ysafbn)
Gman
What is your vision for the future our growing community?
Peace Out, <img src="http://tinyurl.com/ysafbn">
Gman
I would like to just give a word of caution to anyone who believes that 10ah lithium battery is going to come close to a 35ah agm battery in performance. Let me state that either battery when operated at EV discharge rates of 1C or greater will not retain all of their rated capacity. For example a 40 amp discharge rate will be about 1C for the AGM and give about 60-65% of the stated 20hr-rate capacity (~23ah.) The same discharge rate for the lithium battery will be about 4C and will likely give a capacity of about 90-95% of the rated capacity (9.5ah.) This is due to something called the Peukert effect which varies between battery chemistries and manufacturers. The situation changes dramatically when discharge rates go down say if you chose to ride at one-quarter to one-half throttle (8-15 amps). The AGM battery will give a much longer range than the lithium pack.
Lithium is a little tricky in performance too because unlike agm the discharge curve usually is pretty flat. If you don't keep track of how much juice you are using the battery can die quickly without as much warning as a lead acid battery. Also, the BMS may not let you limp home on a deeply depleted battery as well. There is also a big warranty concern and the danger of charger failure. A failed charger can ruin batteries and there are some pretty low quality chinese charger out there. My original charger prematurely killed my first set of scooter batteries. The thought of this happening to over a thousand dollars worth of batteries makes me cringe.
I will be monitoring the forum to see how the lithium pioneers do with their chinese lithium phosphate packs, BMS, and chargers. Hopefully, they will get quality items and keep us updated.