[ausev] Questions for the pros

Mon Jun 30 19:19:59 GMT 2008

Hey Michael,  let me offer a few ideas.

>From my own brutally learned experience, I would not ever attempt an EV conversion without a transmission and clutch (with exceptions).  Your case may be one of the only exceptions: Keeping the vehicle top speed under 45.  True, an AC motor tolerates higher rpms well, but with fixed gearing you have to make an awefull choice upfront.  (I can't vouch for the efficacy of changing gears in a manual transmission without a clutch).  IMHO, transmissions are not going away anytime soon.

I am partial to the Genesis EP SLA batteries. They have great power and excellent inrush tolerance (for regen).  Plus they have a feature, which may or may not be unique among SLAs, that allows a longer absorption charge without overcharging (set your PFC timer to "enabled" to get the absorption charge; I set mine to 4 hours).  I do not have a battery management system yet I observe very little cell to cell drift when charging these in series.  Plus, I just LOVE the top bolt mounting system, as opposed to posts.  To me, its the best thing thing since sliced bread.

Tom

--- rob at zehicle.com wrote:

From: "Rob		" <rob at zehicle.com>
To: "'AustinEV News Announcements and General Discussion'" <ausev at austinev.org>
Subject: Re: [ausev] Questions for the pros
Date: Thu, 26 Jun 2008 20:46:47 -0500

Not as a universal rule, but for an EV with a top speed of 45.  AC motors
have a high top RPM limit so they are better suited for single ratio
operation.  The Tesla only has one gear - their switch from a 2 speed to 1
speed transmission was the cause of their production delay.

-----Original Message-----
From: ausev-bounces at austinev.org [mailto:ausev-bounces at austinev.org] On
Behalf Of evehicle4me at hischopsticks.org
Sent: Thursday, June 26, 2008 6:42 PM
To: ausev at austinev.org
Subject: Re: [ausev] Questions for the pros

Are you suggesting that an AC system does not need a transmission?

Quoting Rob <rob at zehicle.com>:

> Michael,
>
> My own experience suggests that you'd be pushing it.  Best I got the 
> RAVolt to do was 30+ but I'm heavier than a Neon.  I'm confident that 
> you could get DC Pb conversion do this if you beef up the suspension 
> and run over the GVW with lots of lead.  However, you may find the you 
> lose the range after a year months of driving and you'll be short.  In 
> the winter you'll also lose range from the cold.  Remember that Pb 
> batteries fade so your return drive will be sluggish if you are at the 
> end of your range.
>
> Have you considered an AC system?  If your top speed is limited then 
> you'd be able to go direct and avoid the transmission loss.  You'd 
> also get a small boost from regenerative braking with an AC system.
>
> Rob
>
> -----Original Message-----
> From: ausev-bounces at austinev.org [mailto:ausev-bounces at austinev.org] 
> On Behalf Of Michael Bonard
> Sent: Tuesday, June 24, 2008 6:12 PM
> To: AustinEV News Announcements and General Discussion
> Subject: [ausev] Questions for the pros
>
>
> Dear Austin EV members,
>
> My name is Michael Bonard and I am writing from Maryland, in the 
> Washington, DC suburbs.
>
> I have started a conversion of an 2000 Plymouth Neon (2564 pounds curb 
> weight with ICE) and I am looking for recommendations from the pros. 
> Austin EV seems to be the most active group of EV conversion 
> enthusiasts, and this is why I am sending you this message.
>
> The "mission requirement" for my conversion calls for a 34 mile total 
> commute (round trip), mostly flat, top speeds no higher than 45 mph. I 
> would like to reach a 40 miles target to have some safety margin. I 
> have determined the preliminary system composition: 144 V system; FB1 
> 4001 DC Motor; and the rest TBD.
>
> I have the following questions:
>
> - Range: do you think that a 40 mile range could be realistically 
> expected with a 144V system using lead acid flooded batteries, which I 
> understand offer the least cost per kWh today?
>
> - Batteries: what type, manufacturer and make of batteries would you 
> recommend in a 144 V system?
>
> - Battery boxes: Is there an alternate acceptable solution to welding 
> of the battery boxes to the frame? I am not a welder but I can cut 
> steel angles and drill holes for nuts and bolts holding
>
> - Instrumentation: should I reuse the original ICE harness to connect 
> the speedometer to the existing on board computer? I assume that I 
> will have to remove the bulbs in the car instrument panel because with 
> all the ICE sensors removed, there will be lots of alarms showing up! 
> What other instrument panel functions can be re-used?
>
> - Controller: I want to make sure that the equipment I buy is of 
> decent quality. I need your recommendations for the controller: The 
> Zilla controller is very expensive and seems to need special cooling. 
> What do you think about the Curtis 1231C controller? Any other 
> recommendation?
>
> - DC to DC converter and battery charger: again, any suggestion?
>
> - Motor adapter hub: The EV book "Convert It" strongly advises not to 
> use the setscrew securing method for the hub. I have received a couple 
> of proposals with setscrew hubs. What do you think?
>
> - Clutch: some providers propose to remove the clutch; however, I am 
> concerned about having to change gears while going uphill (and there 
> is a hill to climb on the way back home). For me, it is not an option 
> to stop in the middle of the road to change gear. Your thoughts?
>
> - Should I keep the original power steering fluid cooling radiator? My 
> SWAG is that with the very low heat generated by the electric motor 
> system, there is no longer a need to cool the fluid. What do you 
> think?
>
>
> Thanks for taking the time to look at my questions!
>
> Your responses may also help another resident of Maryland who has 
> started the conversion of another Neon 2000. I will share your 
> responses with him.
>
> Michael
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>
>
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