Show us your NiZn battery build- Anyone have any experience?

grindz145

grindz145

1 MW
Joined
Apr 7, 2009
Messages
2,962
Location
Rochester NY
I ran across this post on Engadget today:
http://www.engadget.com/2009/11/09/powergenix-nizn-rechargeable-aa-batteries-finally-some-cells-w/

And I got to searching the forums to see if anyone had built a pack up with this chemistry. I didn't find any mention of anyone who had actually build an pack out of these cells just some PR crap:

http://endless-sphere.com/forums/viewtopic.php?f=14&t=3741&hilit=+nizn

But with the reasonable energy , good power density, and a very reasonable cost I would imagine someone has given these a chance.

Anyone with hands-on experience with this chemsitry?
 
So apparently very few people have had experience with this chemistry.

Here is the Wikipedia article for reference:
http://en.wikipedia.org/wiki/Nickel-zinc_battery

It looks like I can buy them right off the internet in low quantities for ~ $0.60/Wh. I would imagine in qty the price could go lower.

Does anyone have any more insight into this chemistry?
 
they sound good maybe someone should buy some and test them in a bike light. if they really do perform at 9C and 100wh/kg then that would be an amazing leap forward for EV's. it would stop all those people moaning that we are running out of lithium!
 
Yeah, Nickel and Zinc are not precious metals which make the whole chemistry really attractive. I think Apple is using this chemistry for their Macbooks.
 
I have no experience but some quick calculationss do not appear positive in the AA form factor. I calculate around 11000 grams (11 kg for the decimal point impaired, 24 pounds for the metric impaired) for a 10 aH 48V pack or almost double the weight of headways for about double the price.

Unless both the price and performance improve, I'm not going to get any experience.
 
I agree that 60C/ Wh is expensive for the hobbiest, but when you can get that in LOW volume it seems like with some adoption it would end up very cheap. (considering that the A123s in low volume are around $1.30 per w/h) Yes, it is heavier as well, but It seems to me like the cost and C rate performance and longevity could offset the weight a bit.
 
grindz145 said:
It looks like I can buy them right off the internet in low quantities for ~ $0.60/Wh. I would imagine in qty the price could go lower.
Click to expand...

$0.60/Wh is actually only a little higher than Headway prices... but where are you seeing that price? I'm not seeing them for less than $1.20/Wh (PowerGenix AAs). Headways are $0.53/wh plus shipping from here:
http://www.evcomponents.com/ProductDetails.asp?ProductCode=38120S
EDITED: warning: there are a lot of rumors going on about all the good employees leaving evcomponents, and whoever's left is ripping people off

pros/cons...
  • *The powergenix sub-c spec sheet puts the grav density at 69wh/kg - a lot heavier than Headway's 105wh/kg
    *sub-c cell internal resistance <5 mohms - better than Headway's ~10 mohms (AA NiZn cells are <20mohms :? )
    *powergenix cycle life 800-1000 cycles. Headway claims 1500-2000 cycles IIRC
    *It's a lot easier to build a reliable pack out of a few big 3.2v cells with screw terminals than a zillion little 1.6v cells
 
Here is just one of the google shopping results:
http://www.provantage.com/powergenix-f1-0026~7PWGX003.htm

8 Cells X 1.6V X 2.5A-h =32w-h
@~$20 = 20/32 = ~62.5 cents per w/h

-cycle life is less on paper, however I've done a bunch of testing with spinel (liMn2O4) [headway chemistry] and I think those cycle life numbers are on the optimistic side. At high discharge rates they will go much lower
-NiZn has low ESR which means high discharge [C] rates and [possibly] the ability to last longer in a high discharge environment

I completely agree that the form factor is not as favorable, however I'm really interested in the chemistry itself and not necessarily the cells available immediately. After all were talking comparing a price off of a low volume (8 cell) google checkout and a high volume specialty order from China. The bottom line is that I see the possibility for this chemistry to be REALLY inexpensive in volume considering the lack of precious metals even if they are a bit heavier.

http://www.powergenix.com/technology.php
In the chart at the bottom they quote 30-50C per watt hour ; which could mean cheaper than lead acid, with way better performance, and almost twice capacity.

Don't get me wrong, Lithium based chemistries are still the most high performance, but there appears to be benefits to this chemistry for a little less performance at a fraction of the cost.
 
grindz145 said:
http://www.powergenix.com/technology.php
In the chart at the bottom they quote 30-50C per watt hour ; which could mean cheaper than lead acid, with way better performance, and almost twice capacity.

Don't get me wrong, Lithium based chemistries are still the most high performance, but there appears to be benefits to this chemistry for a little less performance at a fraction of the cost.
Click to expand...

The AA cells aren't high power cells - at 20mOhm IR they're going to start heating up at about 2C, not 20C. The 30-50C numbers are referring to the high power sub-C cells that I can't find any prices on. But maybe large format high power cells could be made inexpensively, I have no idea.

Headways are LiFePO4 by the way. You might be right about their cycle life numbers being optimistic, but time will tell. If they really do last 2000 cycles, they could still win on a lifetime cost perspective, even if energy density isn't as important in your application. But size and weight are more important factors than cost in most EV builds, IMHO.

It's still an interesting alternative, especially if you could get large format cells at very low cost. The more choices we have, the better.
 
Ahh, I forgot they were LiFePo4. I do love that chemistry for all out performance.

The website quotes a $0.30 / wh price for EVs (several other manufacturers quote similar prices).
Think of it as an alternative to PbA or NiMH and it starts to make more sense I think.
Again I just love the idea of the lack of precious metals. Lithium is going to get very pricey with demand... That may be far into the future though.
 
NiZn again, via that LinkyDin thingee:
China Guangdong PVD Metallizer Co. at China

Brief introduction to Nickel-Zinc battery for vehicles
The nickel-zinc battery for vehicles produced by our company has strong and lasting power with powerful climbing performance under loading. It has advantages of quick start, easy control of speed with enjoyment and fun in riding or driving. Our nickel-zinc batteries passed by UL, CE certification, even in extreme cases the battery itself does not burn nor burst to ensure the safety of the rider personnel. In addition, the nickel-zinc batteries can work at ambient temperature 110 degrees centigrade and can output strong current under cryogenic temperature as low as minus 40 degrees centigrade. Our technicians have overcome the bottleneck of low temperature operation of batteries, so that electric cars or bicycles can work or operate at any place under any atmosphere and temperature. The nickel-zinc battery for vehicles equipped with specially designed protection circuits is able to prevent battery overcharge and over discharge with long service life.
Features
Click to expand...
 
Seriously??? Nobuddy on ES???

http://en.wikipedia.org/wiki/Nickel%E2%80%93zinc_battery
The nickel–zinc battery (sometimes abbreviated to the chemical symbols for the elements "NiZn") is a type of rechargeable battery that may be used in cordless power tools, cordless telephones, digital cameras, battery operated lawn and garden tools, professional photography, flashlights, electric bikes, and light electric vehicle sectors, among other uses.

Larger nickel–zinc battery systems have been known for over 100 years. Since 2000, development of a stabilized zinc electrode system has made this technology viable and competitive with other commercially available rechargeable battery systems.
Click to expand...

And:
Specific energy 100 W·h/kg
Energy density 280 W·h/L
Specific power > 3000 W/kg
Energy/consumer-price 2–3Wh/US$
Cycle durability 400–1000 cycles[citation needed]
Nominal cell voltage 1.65 V
Click to expand...
 
I've read this thread three times and can't see a single performance/price advantage of using these for an EV application over li-ion.
 
Um... Perhaps read some reviews on Amazon?
http://www.amazon.ca/PowerGenix-ZRPGX-AA8-High-Voltage-Rechargeable-Batteries/dp/B002NJUJ16
 
E.G. A pack of these:
http://www.powergenix.com/files/powergenix/docs/pgx_80ah_prismatic_data_sheet.pdf
 
LockH said:
Um... Perhaps read some reviews on Amazon?
http://www.amazon.ca/PowerGenix-ZRPGX-AA8-High-Voltage-Rechargeable-Batteries/dp/B002NJUJ16
Click to expand...

I read the first one which said they offer no additional capacity over NiMH, are the same weight, are slower to recharge, self-discharge at a higher rate and have a much shorter cycle life.
 
I bought a bunch for round the house, AA's and AAA's
use them in remotes, doorbell, energy monitors, bike lights, toys etc

Problem, cheap ebay cells fine, cheap ebay chargers RUBBISH!, some appliances no good as they dont like them hot off the chager.

eneloop my choice of rechargeable, one back from the super-duper = good value NIMH.
 
Excellent you guyz! (Being one incredibly lazy guy, didn't want to research this stuff myself.)
THANKS! (Responses 50-50 so far maybe.)
 
I found this maker doing cylindrical F cells @ 8, 10 & 12 a/h, maker recommends 0.5C charging - this is fine for an ebike but if used on a car it might mean that charging from a domestic socket (receptacle) would be difficult owing to the heavy current draw(some makers recommend 1C - so even more so). I gather they need constant voltage charging, price @ 60 to 70 % of Lion is a bit more than originally predicted.This is the only reference to them being applied to an ebike I found. I cannot be sure if a BMS is needed, can see some seriesed up in a frame, wonder what the shipping issues are if any
http://www.neucell.net/products.asp
Otherwise I have found the Powergenix 8 a/h flat prismatic cells, these would make a more compact pack, next size Powergenix does is 40 & 80 a/h more car territory
http://www.powergenix.com/files/powergenix/docs/pgx_8ah_prismatic_data_sheet.pdf
I gather that SLA are charged at constant voltage, does anyone know of a particular charger that has an adjustable H.V. cut off as 8s could replace a SLA brick quite closely.
The Powergenix graph shows a good performance at up to 2C steady - while handling much heavier short bursts. Guess it all comes down to how they work in practice! Hope to learn more of them
 
I have been talking to Neu Cell & can firm up on some details

likely cycle life @ 80% DOD 300+ cycles (similar to SLA), but weight about half. A BMS is not needed. I have been offered a sample but would need to produce/modify my own charger to operate as follows

1) Constant current @ 5A with temp monitoring to 50 deg C for first 100 mins (voltage not stated here but I would expect 1.9V max per cell)

2) Constant current @ 5A for 10 mins monitoring temp to 50 deg C & voltage 43.12 max (1.96v per cell) cut off whichever of these values is hit first.

I think the 2nd phase can be omitted at the cost of losing 5% of battery capacity with no harm done (maker does not say this but is published elsewhere)
so the absolute minimum requirement is a constant current module @ 5A with temp monitoring & max V 41.8, & a timer
The real question, is it worth paying about twice the cost of SLA to half its weight & avoid the drooping characteristic, also there is a greater safety element in not needing a BMS to avoid thermal runaway. I have asked for info from Powergenix re their 8A/h & 40A/h prismatics but am still waiting for any reply at all from them
 
25027.jpg


no C rate stated. but still an easy platform for test. 24V at 15Ah would cost 250$ :shock:
anybody willing to try? In the end it would be a funny e-bike pack: 4.0 Kg in total ...

have fun!
 
Here is the proposed F cell pack (if it attaches!) One thing I have learned is that NiZn can only be charged in series strings, so if the Turnigy cells were used it would either need several chargers or each string of the correct voltage charged one after the other, strings could then be paralleled up for discharge (I think). Much cheaper to use cells of the req A/h. I have looked into costs per discharge cycle & where Ni Zn could score is for the occasional weekend ebike user, as unlike Li ion & to a lesser extent LiPo as the cells can store many years as a back up with only shallow or no discharges - providing they are kept topped up. Li ion have only a 2 to 3 yr life even if never put through a discharge cycle. Still working on the charger probs
 

Attachments

  • IMG_0948.jpg
    IMG_0948.jpg
    34.1 KB · Views: 4,877
if that is a 36 V nominal and 10 Ah pack, considering no bms is required and it contain no rare earth metals, doesn't self ignite, doesn't age without being even touched, etc,etc, I would say it is really much interesing :D
possibly in 5 years it could be costing no more than 100 euro .". :mrgreen:

have fun
 
You must log in or register to reply here.

Similar threads

S
I bought a used Chevy Volt - and you probably should too!
2
Replies
26
Views
8,972
neptronix
neptronix
CUDAcores89
Lowest cost per cycle ebike battery
2
Replies
37
Views
5,231
Alan B
Alan B
PacoMarkE
Winter Project! BBS02 DIY Build
2
Replies
39
Views
15,290
LowkeeRider
L
J
Sony US18650NC1 experience
Replies
8
Views
1,993
Allex
Allex
whitepony
Evolve Carbon AT with 50km+ range
2 3 4 5 6
Replies
133
Views
66,782
Voltron
V
Back
Top