# [EVDL] long review on my jeep progress



## EVDL List (Jul 27, 2007)

Though I'd give folks an update on my current status on my '84 Jeep CJ7 conversion
My evalbum page is here for reference: http://www.evalbum.com/4001.

I'm hoping this email helps newcomers by sharing my personal experiences
with parts that can be somewhat easily purchased over the web.


So far I've gone about 40 miles. I've had lots of issues to debug and work out.
I fully expected this since everything on this jeep has been rebuilt or replaced.

Going into the project, I didn't have alot of EV knowledge. I bougt a book
and read what I could on the internet. I couldn't wait to get started. I picked a Jeep
because I wanted to have something that I'd really enjoy driving and
I wanted something unique. I had rebuilt a jeep before so I thought this would help some.

Here's an attempt to catergorize my findings and lessons learned from the decisions I made.

* Picking a Jeep as an EV
- I'm currently getting about 2.3 miles / kWh. I was planning for 2-2.5. I haven't gone on
the highway yet.
- One thing that's cool about having a Jeep as an EV is that I can justify driving something
that would normally only get about 12 miles per gallon. If it wasn't so darn expensive
to hold electricity, one could justify driving a big SUV or whatever... as long as
your have a clean source of electricity I suppose.
- my 5 year old daughter loves that it's a convertable
- My tranny ratios are 4:03, 2.37, 1.5, and 1:1. Axle ratio is 4.10:1

* Warp 9 motor
- I was concerned this motor would be too small, but I'm very happy with the acceleration in 2nd gear.
I don't use 1st.
- So far I don't know if my gearing is good for highway. I've only driven up to 60 mph and the
motor seemed ok (around 2800 RPM). Not sure if I should have used a numerically lower gear ratio (like 3.54).

* Clutchless adapter
- I got my adapter from: http://www.evcouplerconnection.com. Charlie was very helpful and responsive, but I did have
some alighment issues and needed to drill my own holes and have him make me an additional spacer. 
- I'm still not sure I'm perfectly aligned. I doubt it, but the clutchless adapter does allow for some
misalignment.
- I'm now thinking I should have gone with a clutch. I don't really have a problem upshifting, but I haven't 
figured out downshifting. I like to coast in neutral, but then if I try to find a gear without stopping,
I have isssues (grinding). I've tried reving up the motor a bit, but no real success yet.
- I may go back to a clutch for good on road usage. I think clutchless is fine if you're out in the country
or something, but for urban/suburban driving, I'm not so sure. It looks like canev makes a nice adapter,
I just need a different CJ bellhousing which I may be able to find.
- I consider going clutchless a lessoned learned for something not to do.

* Drivetrain/steering/brakes
- I chose to use manual steering. It takes some getting used to, but so far, no regrets.
- I chose to go with manual braks. I think I still have some air in the system to bleed out, but so far, no regrets.
- I had some vibrations. Turns out my driveshaft ubolt straps were too loose. I tightend them. Then found that
my rear axle pinion nut was allowing too much pinion play. This is a big deal and should not have happened.
It's difficult to tighten due to a collapsable bearing spacer. I've had lots of issues with my rear axle
rebuild. We'll have to keep an eye on this.
- The tranny is kind of loud. Originally, I rebuilt it, then took it to a shop. The shop guy said
it might be loud do to some rust on the gears. Some rust was bad and some is acceptable. I should have
had him replace all parts with rust.
- My springs and shocks are stock and seem to work fine with my lithium pack.
- I still have some vibrations. Not sure if I can fix them all.

* Soliton 1 controller
- Love the power. I've set it for 800 motor amps which seems fine. I'm not using liquid cooling yet.
Since I live in Austin, TX, liquid cooling may be in my future.
- I like the web interface. Had some troubles dowloading the latest firmware with my mac, but that's taken
care of now.
- Had some trouble getting the recharge care tach sensor to work. I was running the sensor wires too close
to the motor wires.

* Elcon 2kW charger
- no issues so far
- It puts about 7 amps into my 160V pack with a 110V outlet.
- Haven't tried 220V yet.
- I live the simple enable that is uses. It has 2 wires. When connected, the charger is enabled.
The mini-bms just needs to break this connection to stop the charger.

* Elcon DC/DC converter
- stopped working, probably blew the input caps since I didn't have an inline inductor
- Ordered a belktronics dc/dc converter. It's currently being assembled

* Calb Batteries
- I ordered them indirectly from Keegan
- batteries arrived in a few weeks. They seemed decently balanced
- my mini-bms is saying I'm having some Low voltage issues during higher speeed acceleration. Not sure
if it's the batteries, connnections, or mini-bms at the moment.

* mini-bms
- love the simplicity
- my header board led stopped working and the charger control stopped working for a bit, but is working now.
I'm currently exchanging emails with Dimitri.


_______________________________________________
| Moratorium on drag racing discussion is in effect.
| Please take those discussions elsewhere. Thanks.
|
| REPLYING: address your message to [email protected] only.
| Multiple-address or CCed messages may be rejected.
| UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub
| OTHER HELP: http://evdl.org/help/
| CONFIGURE: http://lists.sjsu.edu/mailman/listinfo/ev


----------



## EVDL List (Jul 27, 2007)

Ben,

Thanks for the play by play, it is very helpful to me. I'm also partial to
jeeps and jeeplike vehicles / convertibles. With the ratios that you
listed, I assume the jeep was a 4cyl to begin with, which would have had
the hydraulic clutch (very easy to modify the linkage there).

What voltage is your battery pack?

Thanks,
Brett



> Ben Jarrrett <[email protected]>wrote:
> 
> >
> >
> ...


----------



## EVDL List (Jul 27, 2007)

Ben,
Very interesting and useful update. I love your conversion and think the most 
important thing is that you pick a vehicle
that is very desirable to your interests. Even if it doesn't have the most 
efficient system due to vehicle weight, aerodynamics, rolling friction etc.
you are still getting the most 'satisfaction per mile' since you picked your 
favorite vehicle! Nice job and hope you continue to enjoy your EV.
Rod


----- Original Message ----
From: Ben Jarrrett <[email protected]>
To: Electric Vehicle Discussion List <[email protected]>
Sent: Mon, April 9, 2012 7:17:25 PM
Subject: [EVDL] long review on my jeep progress



Though I'd give folks an update on my current status on my '84 Jeep CJ7 
conversion
My evalbum page is here for reference: http://www.evalbum.com/4001.

I'm hoping this email helps newcomers by sharing my personal experiences
with parts that can be somewhat easily purchased over the web.


So far I've gone about 40 miles. I've had lots of issues to debug and work out.
I fully expected this since everything on this jeep has been rebuilt or 
replaced.

Going into the project, I didn't have alot of EV knowledge. I bougt a book
and read what I could on the internet. I couldn't wait to get started. I 
picked a Jeep
because I wanted to have something that I'd really enjoy driving and
I wanted something unique. I had rebuilt a jeep before so I thought this would 
help some.

Here's an attempt to catergorize my findings and lessons learned from the 
decisions I made.

* Picking a Jeep as an EV
- I'm currently getting about 2.3 miles / kWh. I was planning for 2-2.5. I 
haven't gone on
the highway yet.
- One thing that's cool about having a Jeep as an EV is that I can justify 
driving something
that would normally only get about 12 miles per gallon. If it wasn't so 
darn expensive
to hold electricity, one could justify driving a big SUV or whatever... as 
long as
your have a clean source of electricity I suppose.
- my 5 year old daughter loves that it's a convertable
- My tranny ratios are 4:03, 2.37, 1.5, and 1:1. Axle ratio is 4.10:1

* Warp 9 motor
- I was concerned this motor would be too small, but I'm very happy with the 
acceleration in 2nd gear.
I don't use 1st.
- So far I don't know if my gearing is good for highway. I've only driven up 
to 60 mph and the
motor seemed ok (around 2800 RPM). Not sure if I should have used a 
numerically lower gear ratio (like 3.54).

* Clutchless adapter
- I got my adapter from: http://www.evcouplerconnection.com. Charlie was very 
helpful and responsive, but I did have
some alighment issues and needed to drill my own holes and have him make me 
an additional spacer. 

- I'm still not sure I'm perfectly aligned. I doubt it, but the clutchless 
adapter does allow for some
misalignment.
- I'm now thinking I should have gone with a clutch. I don't really have a 
problem upshifting, but I haven't 

figured out downshifting. I like to coast in neutral, but then if I try to 
find a gear without stopping,
I have isssues (grinding). I've tried reving up the motor a bit, but no 
real success yet.
- I may go back to a clutch for good on road usage. I think clutchless is 
fine if you're out in the country
or something, but for urban/suburban driving, I'm not so sure. It looks 
like canev makes a nice adapter,
I just need a different CJ bellhousing which I may be able to find.
- I consider going clutchless a lessoned learned for something not to do.

* Drivetrain/steering/brakes
- I chose to use manual steering. It takes some getting used to, but so far, 
no regrets.
- I chose to go with manual braks. I think I still have some air in the 
system to bleed out, but so far, no regrets.
- I had some vibrations. Turns out my driveshaft ubolt straps were too 
loose. I tightend them. Then found that
my rear axle pinion nut was allowing too much pinion play. This is a big 
deal and should not have happened.
It's difficult to tighten due to a collapsable bearing spacer. I've had 
lots of issues with my rear axle
rebuild. We'll have to keep an eye on this.
- The tranny is kind of loud. Originally, I rebuilt it, then took it to a 
shop. The shop guy said
it might be loud do to some rust on the gears. Some rust was bad and some 
is acceptable. I should have
had him replace all parts with rust.
- My springs and shocks are stock and seem to work fine with my lithium pack.
- I still have some vibrations. Not sure if I can fix them all.

* Soliton 1 controller
- Love the power. I've set it for 800 motor amps which seems fine. I'm not 
using liquid cooling yet.
Since I live in Austin, TX, liquid cooling may be in my future.
- I like the web interface. Had some troubles dowloading the latest firmware 
with my mac, but that's taken
care of now.
- Had some trouble getting the recharge care tach sensor to work. I was 
running the sensor wires too close
to the motor wires.

* Elcon 2kW charger
- no issues so far
- It puts about 7 amps into my 160V pack with a 110V outlet.
- Haven't tried 220V yet.
- I live the simple enable that is uses. It has 2 wires. When connected, the 
charger is enabled.
The mini-bms just needs to break this connection to stop the charger.

* Elcon DC/DC converter
- stopped working, probably blew the input caps since I didn't have an inline 
inductor
- Ordered a belktronics dc/dc converter. It's currently being assembled

* Calb Batteries
- I ordered them indirectly from Keegan
- batteries arrived in a few weeks. They seemed decently balanced
- my mini-bms is saying I'm having some Low voltage issues during higher 
speeed acceleration. Not sure
if it's the batteries, connnections, or mini-bms at the moment.

* mini-bms
- love the simplicity
- my header board led stopped working and the charger control stopped working 
for a bit, but is working now.
I'm currently exchanging emails with Dimitri.


_______________________________________________
| Moratorium on drag racing discussion is in effect.
| Please take those discussions elsewhere. Thanks.
|
| REPLYING: address your message to [email protected] only.
| Multiple-address or CCed messages may be rejected.
| UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub
| OTHER HELP: http://evdl.org/help/
| CONFIGURE: http://lists.sjsu.edu/mailman/listinfo/ev

_______________________________________________
| Moratorium on drag racing discussion is in effect.
| Please take those discussions elsewhere. Thanks.
|
| REPLYING: address your message to [email protected] only.
| Multiple-address or CCed messages may be rejected.
| UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub
| OTHER HELP: http://evdl.org/help/
| CONFIGURE: http://lists.sjsu.edu/mailman/listinfo/ev


----------



## EVDL List (Jul 27, 2007)

> Brett Davis wrote:
> 
> > Ben,
> >
> ...


----------



## EVDL List (Jul 27, 2007)

Thanks for the info on clutchless shifting. I will continue to mess around with it to see
if I can master the shifting. In the meantime, I may try to accumulate what I would need
to put the clutch back in and use a ready-made adapter.

-ben



> Jay Summet wrote:
> 
> > -----BEGIN PGP SIGNED MESSAGE-----
> > Hash: SHA1
> ...


----------



## EVDL List (Jul 27, 2007)

Jay's description of clutchless shifting is very good. My del Sol
conversion (www.evalbum.com/2778) is also clutchless. I would rather have
the clutch, but the car is quite driveable. It does take about 4-5 seconds
to shift. It also takes some practice to downshift, so keep trying. Once
the speeds are matched, the gears will mesh.

I tried to have a clutch added to my conversion, but there just wasn't room
in the bell housing.

Mike

> -----Original Message-----
> From: [email protected] [mailto:[email protected]] On
> Behalf Of Ben Jarrrett
> Sent: Monday, April 09, 2012 8:48 PM
> To: Electric Vehicle Discussion List
> Subject: Re: [EVDL] long review on my jeep progress
> 
> 
> 
> Thanks for the info on clutchless shifting. I will continue to mess
around with
> it to see if I can master the shifting. In the meantime, I may try to
accumulate
> what I would need to put the clutch back in and use a ready-made adapter.
> 
> -ben
> 
>


> Jay Summet wrote:
> >
> > > -----BEGIN PGP SIGNED MESSAGE-----
> > > Hash: SHA1
> ...


----------



## EVDL List (Jul 27, 2007)

We make/stock a clutch type adapter for that car.
All our adapters keep the clutch.

BFN
Randy

On 09/04/2012 9:24 PM, Mike Nickerson wrote:
> Jay's description of clutchless shifting is very good. My del Sol
> conversion (www.evalbum.com/2778) is also clutchless. I would rather have
> the clutch, but the car is quite driveable. It does take about 4-5 seconds
> to shift. It also takes some practice to downshift, so keep trying. Once
> the speeds are matched, the gears will mesh.
>
> I tried to have a clutch added to my conversion, but there just wasn't room
> in the bell housing.
>
> Mike
>
>> -----Original Message-----
>> From: [email protected] [mailto:[email protected]] On
>> Behalf Of Ben Jarrrett
>> Sent: Monday, April 09, 2012 8:48 PM
>> To: Electric Vehicle Discussion List
>> Subject: Re: [EVDL] long review on my jeep progress
>>
>>
>>
>> Thanks for the info on clutchless shifting. I will continue to mess
> around with
>> it to see if I can master the shifting. In the meantime, I may try to
> accumulate
>> what I would need to put the clutch back in and use a ready-made adapter.
>>
>> -ben
>>
>>


> Jay Summet wrote:
> >>
> >>> -----BEGIN PGP SIGNED MESSAGE-----
> >>> Hash: SHA1
> ...


----------



## EVDL List (Jul 27, 2007)

>I'm now thinking I should have gone with a clutch. I don't really have a problem upshifting, but I haven't figured out downshifting. I like to coast in neutral, but then if I try to find a gear without stopping, I have issues...

The clutch vs. no clutch issue has been beat to death on this list in
the past. Most folks find out after they assemble an EV with no clutch
that they wish they would have gone with a clutch. If you live in an
area with no hills and never go off-road (it _is_ a Jeep, right?),
then I suppose you can live happily without one. Try downshifting
quickly with no clutch when approaching a steep uphill with traffic
behind you and find out if you can cuss like a sailor  I can't
really imagine trying any kind of serious off-roading without a
clutch. But opinions will vary.

>The tranny is kind of loud. Originally, I rebuilt it, then took it to a shop. The shop guy said it might be loud do to some rust on the gears. Some rust was bad and some is acceptable. I should have had him replace all parts with rust.

This reminded me of working in a muffler shop in the Florida Keys.
Being able to weld rust _to_ rust was a job requirement. Too Funny. If
you locked up a steel bicycle by the seawall in Key West and left it
there for a year there wouldn't be much left other than plastic and
rubber parts.

_______________________________________________
| Moratorium on drag racing discussion is in effect.
| Please take those discussions elsewhere. Thanks.
|
| REPLYING: address your message to [email protected] only.
| Multiple-address or CCed messages may be rejected.
| UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub
| OTHER HELP: http://evdl.org/help/
| CONFIGURE: http://lists.sjsu.edu/mailman/listinfo/ev


----------



## EVDL List (Jul 27, 2007)

> Ben Jarrrett wrote:
> 
> > =
> 
> ...


----------



## EVDL List (Jul 27, 2007)

I find my clutchless Hyundai's syncro rings will spin up my motor on 
down shifts. Just gentle pressure on the shifter toward the gear of 
choice and I watch the motor rpm rise until it slips in. Probably 
wearing out my syncro rings, though. And I have no tail shaft load. 
I don't know whether light weight transaxle oil might be contributing 
to this ease of shifting.

With 800-1000 motor amp setting on my Soliton1, I find satisfactory 
performance using even 4th gear only. I would want an external fan on 
my motor before I did very much of that. But, Ben, I imagine you can 
just use 2nd or 3rd without shifting for much of your in-town driving. 
I believe my 2nd goes up to about 40 mph + and 3rd, 50 mph or more.

I have not encountered an EV parts vendor with better customer support 
and communication than Bryan of Belktronix.

-- 
Willie, ONWARD! Through the fog!
http://counter.li.org Linux registered user #228836 since 1995
Debian3.1/GNU/Linux system uptime 21 days 1 hours 09 minutes

_______________________________________________
| Moratorium on drag racing discussion is in effect.
| Please take those discussions elsewhere. Thanks.
|
| REPLYING: address your message to [email protected] only.
| Multiple-address or CCed messages may be rejected.
| UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub
| OTHER HELP: http://evdl.org/help/
| CONFIGURE: http://lists.sjsu.edu/mailman/listinfo/ev


----------



## EVDL List (Jul 27, 2007)

----- Original Message -----

> From: Martin WINLOW <[email protected]>

> What level is your mini-bms set to for low voltage cutoff/back? I foun=
d mine =

> was set way too high at about 2.9V - should be 2.6V at the most. This may=
be =

> causing your low voltage warning issues.

is this adjustable at all? I low voltage alarm under heavy acceleration =
(anything higher than 3c), to the point where if I know I'm going to be 'ag=
gressive' during a drive, I'll unplug my warning buzzer. Is there any wa=
y to determine exactly what voltage the MiniBMS low voltage alarm is set at=
? I only have pack level voltage monitoring, and my cells are not very w=
ell matched so it's hard to know individually where they are just on pack v=
oltage alone, but I find I trigger the low voltage alarm at around 2.75vpc =
(132v for the 48 cell pack). Individual cells may be significantly lower=
, I have IR's that are all over the map.


david.
http://www.evalbum.com/4021


_______________________________________________
| Moratorium on drag racing discussion is in effect.
| Please take those discussions elsewhere. Thanks.
|
| REPLYING: address your message to [email protected] only.
| Multiple-address or CCed messages may be rejected.
| UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub
| OTHER HELP: http://evdl.org/help/
| CONFIGURE: http://lists.sjsu.edu/mailman/listinfo/ev


----------



## EVDL List (Jul 27, 2007)

> David Ladd wrote:
> 
> > ----- Original Message -----
> > =
> ...


----------



## EVDL List (Jul 27, 2007)
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----------



## EVDL List (Jul 27, 2007)

> On 10 Apr 2012 at 18:21, Martin WINLOW wrote:
> 
> > For my money, bottom balancing to 2.6V and then charging until the first cell
> > hits 3.8V or the cell capacity - which ever happens first - is the way to go.
> ...


----------



## EVDL List (Jul 27, 2007)

> David Ladd wrote:
> > if I were reversing a cell, isn't that fatal? ??My cells bounce right back after a hard pull, I think I'm just sagging them down. ??I have one cell with an IR of 2.2, and a handfull with IR's of 1.1-1.3 ??while the rest are at the more normal 0.6-0.8 range. ??These cells with higher IR will always sag further than the good cells, right? ??And I believe I'm correct that having mismatched cells like this in series is not going to cause a bad cell to hurt a good cell, right?
> >
> > I have done capacity and IR testing on all my cells, so i know which are weak. ??They consistently fall a little behind the 'good' cells during normal use, I top them off with a power supply every once in a while when I observe that the red lights are not coming on at end of charge. ??To me, this is easier than bottom balancing, since I can just check the lights at end of normal charge every few days and keep tabs of when I need a 'top off.'
> ...


----------



## EVDL List (Jul 27, 2007)

David,
I'm not advocating either way, but I think the argument for bottom balancing is that it's hard to know when, as you write, "the first one hits its minimum." I'm assuming that you mean its minimum voltage, but that is variable depending on current. With bottom balancing, every cell should get near empty there at about the same time, so you reduce the risk of driving a weak cell empty before the others, thus possibly destroying it.

Bill 

_______________________________________________
| Moratorium on drag racing discussion is in effect.
| Please take those discussions elsewhere. Thanks.
|
| REPLYING: address your message to [email protected] only.
| Multiple-address or CCed messages may be rejected.
| UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub
| OTHER HELP: http://evdl.org/help/
| CONFIGURE: http://lists.sjsu.edu/mailman/listinfo/ev


----------



## EVDL List (Jul 27, 2007)

This is only important for those of us that fly without instruments,
I mean without BMS that warns you when the first cell hit Low Voltage
threshold. Because with BMS, you do not care about top or bottom
balancing, just that you stop when the BMS tells you to.
Most BMS'es actually automatically enforce a power reduction to
back off the load when it detects low voltage.... 


Cor van de Water
Chief Scientist
Proxim Wireless Corporation http://www.proxim.com
Email: [email protected] Private: http://www.cvandewater.com
Skype: cor_van_de_water XoIP: +31877841130
Tel: +1 408 383 7626 Tel: +91 (040)23117400 x203 

-----Original Message-----
From: [email protected] [mailto:[email protected]] On
Behalf Of Bill Dennis
Sent: Wednesday, April 11, 2012 1:23 AM
To: Electric Vehicle Discussion List
Subject: Re: [EVDL] long review on my jeep progress

David,
I'm not advocating either way, but I think the argument for bottom
balancing is that it's hard to know when, as you write, "the first one
hits its minimum." I'm assuming that you mean its minimum voltage, but
that is variable depending on current. With bottom balancing, every
cell should get near empty there at about the same time, so you reduce
the risk of driving a weak cell empty before the others, thus possibly
destroying it.

Bill 

_______________________________________________
| Moratorium on drag racing discussion is in effect.
| Please take those discussions elsewhere. Thanks.
|
| REPLYING: address your message to [email protected] only.
| Multiple-address or CCed messages may be rejected.
| UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub
| OTHER HELP: http://evdl.org/help/
| CONFIGURE: http://lists.sjsu.edu/mailman/listinfo/ev

_______________________________________________
| Moratorium on drag racing discussion is in effect.
| Please take those discussions elsewhere. Thanks.
|
| REPLYING: address your message to [email protected] only.
| Multiple-address or CCed messages may be rejected.
| UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub
| OTHER HELP: http://evdl.org/help/
| CONFIGURE: http://lists.sjsu.edu/mailman/listinfo/ev


----------



## EVDL List (Jul 27, 2007)

>> For my money, bottom balancing to 2.6V and then charging until the 
>> first cell hits 3.8V or the cell capacity - which ever happens first - is
the way to go.

>I know we've beaten this issue to death on the EVDL, but I'll be darned if
I can see what difference it makes whether you top or bottom balance, as
long as you monitor all the cells and stop discharging when the first one
hits its >minimum. 

I'm with you David. Top balancing is a lot easier to accomplish,
accomplishes the same thing, can be done every time you do a full charge,
top balancing boards are readily available. 


Sincerely,
Mark Grasser



_______________________________________________
| Moratorium on drag racing discussion is in effect.
| Please take those discussions elsewhere. Thanks.
|
| REPLYING: address your message to [email protected] only.
| Multiple-address or CCed messages may be rejected.
| UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub
| OTHER HELP: http://evdl.org/help/
| CONFIGURE: http://lists.sjsu.edu/mailman/listinfo/ev


----------



## EVDL List (Jul 27, 2007)

________________________________
> From: Willie McKemie <[email protected]>

>David, how did you measure internal resistance? 

I tested all 48 cells individually with a Cellpro Powerlab 6 battery 'works=
tation'. These were full cycle tests, charge to full, discharge, re-char=
ge to full. It measures the IR during the charge cycle. I was able to=
get capacity and IR for all of my cells. In my case, discharging from 3=
.60 to 2.80v got me capacities ranging between 125 and 135ah for 130ah CALB=
cells, so I am limiting my total Ah usage to 100ah.. This testing took =
about 8 hours/cell, so not a trivial operation...

>
>How did you come to have mis-matched cells? Mine came from at least =

>three different purchases.

I don't know, I bought the car and batteries used. However, there is no =
indication of abuse, they were all purchased at the same time, and they had=
a MiniBMS installed all their life.

>
>I have never considered low voltage alarms under heavy current draw to =

>be, well, "alarming" as long as the voltage comes back up as soon as =

>current demand diminishes.

that's my current (get it?) thinking. I have yet to get a low voltage wa=
rning during normal driving (which see's 1-2c typically), even on a fairly =
discharged pack. Though I've never been below about 70% discharged.

Hey Ben, sorry for drifting so far off topic! Love your Jeep, btw. 

david.
http://www.evalbum.com/4021


_______________________________________________
| Moratorium on drag racing discussion is in effect.
| Please take those discussions elsewhere. Thanks.
|
| REPLYING: address your message to [email protected] only.
| Multiple-address or CCed messages may be rejected.
| UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub
| OTHER HELP: http://evdl.org/help/
| CONFIGURE: http://lists.sjsu.edu/mailman/listinfo/ev


----------



## EVDL List (Jul 27, 2007)

If using a BMS that monitors each cells voltage the BMS system will tell you
when any cell gets to the low point.


Sincerely,
Mark Grasser


-----Original Message-----
From: [email protected] [mailto:[email protected]] On Behalf
Of Bill Dennis
Sent: Tuesday, April 10, 2012 3:53 PM
To: Electric Vehicle Discussion List
Subject: Re: [EVDL] long review on my jeep progress

David,
I'm not advocating either way, but I think the argument for bottom
balancing is that it's hard to know when, as you write, "the first one hits
its minimum." I'm assuming that you mean its minimum voltage, but that is
variable depending on current. With bottom balancing, every cell should get
near empty there at about the same time, so you reduce the risk of driving a
weak cell empty before the others, thus possibly destroying it.

Bill 

_______________________________________________
| Moratorium on drag racing discussion is in effect.
| Please take those discussions elsewhere. Thanks.
|
| REPLYING: address your message to [email protected] only.
| Multiple-address or CCed messages may be rejected.
| UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub
| OTHER HELP: http://evdl.org/help/
| CONFIGURE: http://lists.sjsu.edu/mailman/listinfo/ev

_______________________________________________
| Moratorium on drag racing discussion is in effect.
| Please take those discussions elsewhere. Thanks.
|
| REPLYING: address your message to [email protected] only.
| Multiple-address or CCed messages may be rejected.
| UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub
| OTHER HELP: http://evdl.org/help/
| CONFIGURE: http://lists.sjsu.edu/mailman/listinfo/ev


----------

