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TomT
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Delivery Date: 01 Mar 2011
Leaf Number: 000360
Location: California, now Georgia
Contact: Website

Re: 12 V battery - why?

Sat Apr 18, 2015 8:00 pm

Originally it was going to be 48 volts to gain more advantage. Later they dropped it to 36 because of the aforementioned issues... Even at that, it died... I don't know why as it seemed a good idea. Perhaps partly because of the incompatibility with virtually everything else out there.

alanlarson wrote:Looking around, it appears that it was a 42 volt system, just as current cars are a 14 volt system. This kept the charging voltage around 42 volts, and was a "36 volt" battery. The voltages were all 3 times current values for 12 volt systems.
59,991 miles/12 bars/289 Gids/68.54 AHr/101% SOH/101.64% Hx 7May15 w/ new Lizard (barely made the warranty).
71,770 miles/12 bars/256 Gids/59.04 AHr/88% SOH/87.92% Hx 3Mar16 at lease return.

Now driving a 2016 Volt Premier.

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Nubo
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Joined: Fri May 28, 2010 11:01 am
Delivery Date: 31 Oct 2014
Location: Vallejo, CA

Re: 12 V battery - why?

Sat Apr 18, 2015 9:46 pm

gbarry42 wrote:This isn't a deep-cycle issue. It's an improper charge level issue. Unless AGM doesn't care about being half charged, I don't see how this solves the problem. There must be some attribute I don't know about.


There is a deep-cycle issue separate from any charge-voltage parameters. Long periods of *no* charging during which the battery is slowly draining. This is exacerbated by periods of high current demands during telematics and also because top-off charging during extended parking does not happen if the car is plugged-in.
I noticed you're still working with polymers.

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gbarry42
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Location: Moonlight Beach

Re: 12 V battery - why?

Sat Apr 18, 2015 11:39 pm

I see. So, maintaining the battery at 60% charge is kind of like one big four year long deep cycle :roll:
And there goes the first capacity bar! At 24,000 mi on 9/9/2013.
Second bar at 30,500 mi on 2/7/2015.

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Nubo
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Joined: Fri May 28, 2010 11:01 am
Delivery Date: 31 Oct 2014
Location: Vallejo, CA

Re: 12 V battery - why?

Sun Apr 19, 2015 2:27 pm

gbarry42 wrote:I see. So, maintaining the battery at 60% charge is kind of like one big four year long deep cycle :roll:


You're confusing cause and effect. But this is really OT for this thread and my fault for taking it off track.
I noticed you're still working with polymers.

2k1Toaster
Posts: 482
Joined: Mon Nov 18, 2013 5:45 pm
Delivery Date: 12 Nov 2013
Leaf Number: 420903

Re: 12 V battery - why?

Tue Apr 28, 2015 11:10 am

TomT wrote:Originally it was going to be 48 volts to gain more advantage. Later they dropped it to 36 because of the aforementioned issues... Even at that, it died... I don't know why as it seemed a good idea. Perhaps partly because of the incompatibility with virtually everything else out there.


Believe me, it is not dead...

And some of the new designs will make it nearly impossible to do even simple car modifications because of the data and power distribution networks. It is super cool from an engineering standpoint. Irritating from a consumer level car hobbyist viewpoint.
2013 Nissan Leaf SV with every option
2013 Prius C Package 4
2012 Lexus RX450h
2006 Prius Gen II, pIV
2005 Honda Civic Hybrid
2001 Honda Civic EX
1997 Honda Prelude SH
1981 DeLorean DMC12
and more...

User avatar
TomT
Posts: 10610
Joined: Sun Aug 08, 2010 12:09 pm
Delivery Date: 01 Mar 2011
Leaf Number: 000360
Location: California, now Georgia
Contact: Website

Re: 12 V battery - why?

Tue Apr 28, 2015 11:30 am

No, not today, but it was for MANY years after BMW first proposed then dropped it... The technology is much different today than it was then.

2k1Toaster wrote:
TomT wrote:Originally it was going to be 48 volts to gain more advantage. Later they dropped it to 36 because of the aforementioned issues... Even at that, it died... I don't know why as it seemed a good idea. Perhaps partly because of the incompatibility with virtually everything else out there.
Believe me, it is not dead...
59,991 miles/12 bars/289 Gids/68.54 AHr/101% SOH/101.64% Hx 7May15 w/ new Lizard (barely made the warranty).
71,770 miles/12 bars/256 Gids/59.04 AHr/88% SOH/87.92% Hx 3Mar16 at lease return.

Now driving a 2016 Volt Premier.

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