Upgraded ZAP to Lithium: BUT Too Good to be true?

Puppyjump

100 W
Joined
Sep 3, 2008
Messages
190
Hi All.

I upgraded my ZAP PK from lead acid to Lithium. Installed Elite Power Solutions 72V 100AH system that includes 6 packs of 4 cells already strapped, BMS with dashboard video display, Charger. All in a complete kit. I've been waiting for someone to finally offer a LiFePO4 system as complete, especially the strapped cells and BMS. The cells made by GBS are very well designed, too. The battery posts each have 4 bolts for securing connectors, and each cell BMS board nests between the cell posts and is secured with two of the screws. No customization and fabrication is required as would be the case if I just bought a case of 24 Thundersky cells and then tried to source a charger and BMS, and then kludge together a cell strapping solution etc.

>No, I am not trying to advertise and spam the EPS product, and I have nothing to gain, but I am simply stating how easy this particular product is, and that it's been what I've been waiting for for the above reasons<

Some stats:
Lead acid pack
84V (upgraded)
630 pounds (QTY=7 150AH batteries)
10-15 mile range
Pack Lifetime about 1 year at 6000 miles, even with proper care with prompt recharging and never depleting below 80% DOD. I've gone thru 3 packs already at $1500 per pack.

Lithium pack
LiFePO4 Chemistry: Very safe with no fire risk compared to Lithium Ion
72V, 100AH
150 pounds
35 mile range
Lifetime? Rated at 3000 charges at 80% DOD but it's unknown how long it will last.

Driving impressions: Astounding difference!
>My ZAP feels much "lighter on its feet".
> It's a very suitable local commuter now.
>It requires much less pedal pressure for braking and the ZAP actually has acceleration now.
> Good Hill climbing: I visited a friend who lives up a very steep grade. My ZAP made it up the grade (but it pulled 250 amps at 10-15 MPH so I'd not want to do this very often). Google Maps in San Jose the intersection of Skyview Dr and Sierra Rd. The climb begins at Fulbar Ct and gains an altitude along Sierra Rd of about 450 feet in a very short distance. My friend said this climb is the steepest road in the county. I never tried it with the lead acid pack but I doubt I could have done it.
>The ZAP will attain a speed of 30 MPH from a dead stop climbing to the top of a standard overpass hill.
>If approaching an overpass hill at 40MPH, the ZAP will slow to 35 MPH at the top.
>Top speed on level road is 40 MPH.

I can expect:
longer brake pad life
longer wheel bearing life
safer shorter stopping distance (substandard with lead acid)

TOO GOOD TO BE TRUE?????

If this pack actually has a good cycle lifetime (and I think it will), then LiFePO4 is essentially perfect for EVs. However, there is a PATENT WAR pending for LiFePO4 chemistry. University of Texas claims rights to this chemistry, and they've been trying for a number of years to get a patent on LiFePO4. According to Wiki the case was dismissed but UT reworded the claim so it's back in court with a suit against A123. There's an energy company in Canada also trying to secure this patent too.
In my opinion, If ANY entity gains exclusive rights to LiFePO4 then it won't be long before a front company for Big Oil buys the patent with an offer that can't be refused and then makes these batteries unavailable (as was done with NiMH cells from the RAV4 EV). LiFePO4 batteries are just too perfect for EVs and can be a game changer for transportation and thus a threat to Oil profits. Forgive my paranoia, but there is at risk trillions of petrodollars revenue.

Pics of old lead acid pack and new LiFePO4 pack in my ZAP:
View attachment 3
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LiFePO4 is a dead chemistry.

NMC is currently where its at.

NMC will hopefully be dead by the end of this year.
 
how far into the discharge were you when the hill made you pull 250A? did you see how low the voltage dropped when under that load? that would be useful to know to evaluate the C rating of those big prismatic cells.

the clamping plates on the ends are very well designed, no waste of metal and used an extrusion to form the strongback and then used steel for the clamps.

i once tried to get someone with a ZENN to consider converting to lifepo4. the peppy is because you have a lot more voltage still available with lithium ion chemistry because the peukert effect eats up so much of the voltage on lead acid packs.

i saw a zap drive by this morning about 5:30, so neat to see EV's in use.
 
dnmun said:
how far into the discharge were you when the hill made you pull 250A? did you see how low the voltage dropped when under that load? that would be useful to know to evaluate the C rating of those big prismatic cells.

the clamping plates on the ends are very well designed, no waste of metal and used an extrusion to form the strongback and then used steel for the clamps.

i once tried to get someone with a ZENN to consider converting to lifepo4. the peppy is because you have a lot more voltage still available with lithium ion chemistry because the peukert effect eats up so much of the voltage on lead acid packs.

i saw a zap drive by this morning about 5:30, so neat to see EV's in use.

Voltage dropped from 79V to 72V under the 250A load. Given the cells are 100AH, I don't like loading them at 250A.
 
liveforphysics said:
LiFePO4 is a dead chemistry.

NMC is currently where its at.

NMC will hopefully be dead by the end of this year.

Sounds intriguing. Is NMC a safe chemistry? My ZAP only has a 7.2 KWH pack but a "real" EV will have about a 30 KWH pack. I would not want to be in a vehicle if that pack lights up. I saw a LiPO pack spontaneously burn up in a RC helicopter, and that pack was only half the size of a pack of cigarettes. That pack burned up violently!!!
Also, what is the NMC cycle life?
 
Also, what is the NMC cycle life?

He's not allowed to say anything about it because of NDC agreements. All he can do is tell us it's better than whatever we're using. But if it's so great, WHY AREN'T YOU USING IT?
 
Next up, lithium-vanadium phosphate?
http://www.americanvanadium.com/lithium-vanadium-batteries.php
Meanwhile, Japan's GS Yuasa Corporation (GSY) announced at the end of Q3 2010 that it would develop lithium rechargeable batteries using lithium-vanadium phosphate.

A prototype of GSY's lithium-vanadium phosphate battery showed a 20% output gain compared to a lithium iron phosphate battery. GSY indicated further benefits include improved safety and lower production costs.

Anyway, back on topic, yah, if the new pack goes on to outlast many lead packs (in addition to the other performance benefits) you'll be grinning harder than the folks still running floodies... Congratulations!

locK
 
Until someone credible makes claims about when Nickel-manganese-cobalt (NMC) batteries will be available to us at all, why should we give a flying funk?
 
The only reason I mentioned NMC is in response to this:


Puppyjump said:
In my opinion, If ANY entity gains exclusive rights to LiFePO4 then it won't be long before a front company for Big Oil buys the patent with an offer that can't be refused and then makes these batteries unavailable (as was done with NiMH cells from the RAV4 EV). LiFePO4 batteries are just too perfect for EVs and can be a game changer for transportation and thus a threat to Oil profits. Forgive my paranoia, but there is at risk trillions of petrodollars revenue.


I was just saying, oil companies couldn't care less about LiFePO4 or the lawyers that ruined the couple of years it could have had a moment in the sun.

For us ES DIY folk, by all means, use anything that stores your energy and gets you around, LiFePO4 is a fine choice.

If you're an OEM however, you are currently building your production vehicles or engineering prototypes with NMC, and you had better be laying the hooks in to grow past NMC or you're going to be left behind (or collapse before ever delivering, as the EV start-ups that tried to lock into LiFePO4 have.)
 
liveforphysics said:
The only reason I mentioned NMC is in response to this:


Puppyjump said:
In my opinion, If ANY entity gains exclusive rights to LiFePO4 then it won't be long before a front company for Big Oil buys the patent with an offer that can't be refused and then makes these batteries unavailable (as was done with NiMH cells from the RAV4 EV). LiFePO4 batteries are just too perfect for EVs and can be a game changer for transportation and thus a threat to Oil profits. Forgive my paranoia, but there is at risk trillions of petrodollars revenue.


I was just saying, oil companies couldn't care less about LiFePO4 or the lawyers that ruined the couple of years it could have had a moment in the sun.

For us ES DIY folk, by all means, use anything that stores your energy and gets you around, LiFePO4 is a fine choice.

If you're an OEM however, you are currently building your production vehicles or engineering prototypes with NMC, and you had better be laying the hooks in to grow past NMC or you're going to be left behind (or collapse before ever delivering, as the EV start-ups that tried to lock into LiFePO4 have.)

Sorry, I was tired and cranky when I posted earlier. Yes, planning for future batteries seems a moving target.
 
liveforphysics said:
The only reason I mentioned NMC is in response to this:


Puppyjump said:
In my opinion, If ANY entity gains exclusive rights to LiFePO4 then it won't be long before a front company for Big Oil buys the patent with an offer that can't be refused and then makes these batteries unavailable (as was done with NiMH cells from the RAV4 EV). LiFePO4 batteries are just too perfect for EVs and can be a game changer for transportation and thus a threat to Oil profits. Forgive my paranoia, but there is at risk trillions of petrodollars revenue.


I was just saying, oil companies couldn't care less about LiFePO4 or the lawyers that ruined the couple of years it could have had a moment in the sun.

For us ES DIY folk, by all means, use anything that stores your energy and gets you around, LiFePO4 is a fine choice.

If you're an OEM however, you are currently building your production vehicles or engineering prototypes with NMC, and you had better be laying the hooks in to grow past NMC or you're going to be left behind (or collapse before ever delivering, as the EV start-ups that tried to lock into LiFePO4 have.)

I politely disagree with your argument on this fine point: If it's true NMC is superior than LiFePO4, it doesn't matter because LiFePO4 is ALREADY good enough for most of us. So what would happen is this: The patents for BOTH LiFePO4 and NMC will be purchased by Big Oil. They certainly have the funds to engage in this sort of activity w/o significantly affecting their profits. We can only hope enough EVs get sold to reach critical mass for public awareness and acceptance to break the 100 year old petroleum monopoly on motive energy. So far the Leaf, a fantastic car, is being produced is pitifully small numbers.
 
Fortunately big oil is making so much money nowdays because of the perception that the price is going up, they may not give a damn about any battery.
Plus the fact that china will simply say come on over and sue me in china court, and tell the patent owner to hug off. I think lifepo4 will be around for awhile, even if it seems lame compared to the new stuff. As fast as golf courses wear out their lead, I'm quite suprised that the golf carts aren't all running lifepo4 now. Big busy courses would love lifepo4 carts.
 
Hahah you guys are funny
Whats next
LMP
The mythical kolibri hummingbird liquid not ha solid state metal polymer battery whose patent is covered by a patent owned by canadas electric utility and some french conglomerate owned by royal french family who makes rolling papers and is the largest capacitor sepArator producer worldwide

I aint sure neither
 
This battery pack will last a long time if you cut your maximum discharge to 2C and don't exceed 1C very often.

What i mean to say is that a >150AH lifepo4 setup would help if you want to get the '1000 rated cycles'. Lifepo4 cycles are rated at 1C or below 1C.. you are pushing this pack intermittently to 2.5C... not too far, but what are your cruising amps and how often do you hit that current limit?
 
liveforphysics said:
LiFePO4 is a dead chemistry.

NMC is currently where its at.
NMC will hopefully be dead by the end of this year.

Please, do tell where we can get affordable NMC... or NMC at all these hobbyist applications.
Until then.. reports of Lifepo4's death are greatly exaggerated :mrgreen:

I've tried to get my hands on this NMC stuff. Nobody will talk to me or give me a real price. I'd love to start a business selling eBike kits with NMC packs right now.

LFP, you said you'd talk to hobbyking about NMC batteries a few months ago. What sort of response did you get?
 
neptronix said:
This battery pack will last a long time if you cut your maximum discharge to 2C and don't exceed 1C very often.

What i mean to say is that a >150AH lifepo4 setup would help if you want to get the '1000 rated cycles'. Lifepo4 cycles are rated at 1C or below 1C.. you are pushing this pack intermittently to 2.5C... not too far, but what are your cruising amps and how often do you hit that current limit?
My cruising amps is about 80 to 100 amps. Accel amps about 150 to 200. Usually I will only draw about 30AH out of the 100AH pack before I recharge it. So I hit the 2C+ value frequently, from every stoplight, etc but I will draw that for about 15 seconds each time.
It would be nice to have a supercapacitor bank to handle the high draw rates
 
That isn't too bad then. But another 25-50ah would help. Even less voltage sag.
 
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