Guys, I'm brand new to your forum, but I thot someone might be able to help me determine if I should try to use some Evertroll NiZN batteries in my small EV that I'm building. I was given (free) 8 of these 12v batteries. They were at various states of discharge from 12.15v to 6v. I charged then using my auto battery charger and most of them came up to and hold at 11.3-11.8v. This battery was designed for electric trolling motors and each battery had a removable battery management charger installed on the top that plugs into a 120v socket. I have 1 (non-functioning) BM charger, but I may be able to find some more.
Here's some comments I found on a website:
Evertroll batteries cannot serve as cranking batteries because they can’t be charged by the engine’s alternator. They can only be charged with the special AC charger included with each battery.
I just learned of PowerGenix, who is developing a Nickel Zinc battery (NiZN). It's interesting to see a new company try and develop this chemistry, after the spectacular failure of Evercel.
According to the MB100-12 owners manual, these batteries are capable of of 15.6v max and as low as 7.6v. They are 85Ah and can be rapidly discharged up to 400A. They only weigh about 45 lbs and are a group 31 size (12"L x 7"W x 9"H). The manual says that they can go to sleep if not used (as in my case), and need to be discharged and recharged 3 to 5 times to wake them up. It says to charge them for 550 minutes at 11 amps using a constant current (CC) charge method which my auto charger can do.
What can I use for a charger if I can't find the originals? How should I discharge these? Are they useable if I can get them up to only 12-13v? I plan to use a 72V system, so I assume they all need to be equal.
Thanks for your help.
Chuck H
p.s. I'm a member of SEVA (Seattle EV Assoc)if anybody is in this area.
Welcome abroad, Chuck
First let me say that you picked the best web site for electric powered vehicle development .
I have been working with Nickel-Zinc chemistries for almost 10 years and still fell that there is a lot to learn ,
the chemistries is very good if taken care of properly and match with a appropriate BMS ( have one in the design stage for the past couple years ,final stage of debugging the software, the power section worke very well ).
Evercel failure was precipitated by not accepting the peculiarity of the Nickel-Zinc chemistries making it mandatory the use of dependable BMS for any system beyond a couple cells.
In my humble opinion they also targeted the wrong market,going up against the lead-acid on price,instead of going up against the Nickel-Cad chemistries using the environmental issue ,lighter weight , lower cost factor , well that is history .
The 8 packs that you acquired , do you happen to know when where they manufacturer ?.Are they 7 or 8 cells pack ?
Do you have access to each individual cell connection on the 12 pack ?
I highly recommend that until you can take a impedance ( or resistance ) readings of the cells that
you do not charge or discharge them .The reason is very simple .
If the cell have a high impedance and you attempt to charge them , quickly ( most fast charger will applied a higher
than normal voltage to the cell , ) then the current being impressed onto high impedance will generate a lot of heat
that is one thing you definitely want to avoid .
You mentioned that you place them on one of your charger and afterward you got 11.3 to 11.8 volt, not a good sign
my guess one or more cell are not coming up , or are shorted .
Do not despair , have lot of very old pack that I managed to bring back from the dead .
Some packs that I started with had cell with 0 Volt and impedance in the 15 to 25 milliohms,when I got done
with my rejuvenating process,those same cells are down in the 2-3 milliohms area and delivering original A/H capacity .
The process is very time consuming and not to easy, but ounce they regain their low impedance they
will stay there unless you abused them.
Have a lot information and pictures on the Nickel-Zinc pack , if you e-mail directly and give me a e-mail
I will forward you Test Report performed by "ZSW " ( German Solar Energy research outfit in the late 1999 giving the Nickel-Zinc chemistries high praises .
My wife and I use 2 Oxygen Lepton-E scooter( weather permiting) with over 1,600 combined miles with packs manufactured over 7 years ago giving me full original capacity 30-34 A/H .
Will attempt to upload this report to the site do not know if it will allow me due to its size .
Regards
Andre
HEAT & LOSS & INEFFICIENCY RELATED DIRECTLY to IMPEDANCE
Where'd you get them from? I didn't know they were available yet. Or did you just get them cause you know somebody?
I'd say: "Yes. Try them out. Then report back." ;)
The author of this post isn't responsible for any injury, disability or dismemberment, death, financial loss, illness, addiction, hereditary disease, or any other undesirable consequence or general misfortune resulting from use of the "information" contai
Andre, thanks for your assistance. Please email me at c.harbert1 [at] verizon.net. I would very much like to know how to save these batteries. The picture in the owners manual is not of the Evertroll, so I doubt they are the 15.6 v 85Ah ones, but I don't know. According to Powerstream (http://www.powerstream.com/Compare.htm) they are only 22 Ah.
I tested the batteries with my ohm meter and they read between 625 to 950 ohms between terminals, if I read it correctly.
I believe these were made around 2003-5 for boat trolling motors before Evercel went out. There's no model or serial number on them. They just say 12 volt Evertroll, and they are a fully sealed battery (no access to cells)
Chuck H