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Has anyone looked into how difficult it would be to add or replace batteries to gain range in EV mode and get rid of the ICE? If I could get the range up to 100-150 miles in EV mode I would have no need for the ICE. Is it feasible to pull out the ICE and replace it with more batteries? or replace the existing batteries with more efficient new batteries?

Bobby
 

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Getting rid of the ICE would be a difficult task. The HCU that controls the ICE would need to be reprogrammed and all of the diagnostic messages that the HCU puts out for the ICE would have to be masked so they do not show on the cluster.
 

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You can fit 40-60kWH in the tunnel using production OEM grade modules that weigh around the same as the current A123 pack (~600lbs). Might as well do that and keep the ICE or swap with a smaller one that will allow for greater exhaust volume.

HCU/ECM do not need to be programmed, best not to touch that. You can control the functionality of the vehicle without touching the HCU.
 

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You can fit 40-60kWH in the tunnel using production OEM grade modules that weigh around the same as the current A123 pack (~600lbs). Might as well do that and keep the ICE or swap with a smaller one that will allow for greater exhaust volume.

HCU/ECM do not need to be programmed, best not to touch that. You can control the functionality of the vehicle without touching the HCU.
I know you guys are working on a larger battery pack. And I am seriously considering putting down the $1000 to reserve one. What's your estimate on timing?
 

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6 Months or so depending on the number of reservations. We have a double capacity pack we are working on. A possible scenario would be to allow the 30kWh reservations move up to the 40kWh. This will take a bit longer vs the 30kWh to validate, due to a different thermal setup. Feel free to email or private message for a more in-depth conversation.
 

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6 Months or so depending on the number of reservations. We have a double capacity pack we are working on. A possible scenario would be to allow the 30kWh reservations move up to the 40kWh. This will take a bit longer vs the 30kWh to validate, due to a different thermal setup. Feel free to email or private message for a more in-depth conversation.
do you convert the existing packs or do you just provide a brand new pack the fits the existing tunnel ?
 

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Two options are planned:

1. We ship our pack to the customer and the A123 pack is sent to us. Customer is rebated a "core" charge. If they are so inclined, they can remove the modules and BMS. The only thing of value to us is in the enclosure.

2. We ship the customer our pack and customer can keep their own pack.

The only value of the existing A123 pack is in the tray and cover. Everything else is gutted and recycled. We do have our own tray and cover design but at our volumes it is a fair bit more expensive than re-purposing existing enclosures with our battery system.

Interesting Data point- as our pool of TOM users has gotten larger over the past few months, we have received feedback that being able to hold and rebuild miles on long expanses of highway has actually reduced many owners need for a larger pack. Go figure. :blush:
 

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Correct me if I am wrong, but u never get free energy, that's just a basic law of science. Energy is converted from one form to another ad some is lost is the process. So, if the new module holds charge while driving on ICE, what is the real point of using the ICE to charge and hold the charge when gas is used in the process to charge the battery??!! Am I missing something here? I know you may wish to preserve your battery miles for stop start traffic ad use ICE for highway driving but nonetheless the difference is somewhat minimal and what's the point of re-charging or holding charge while using ICE? Unless the ICE is super efficient and in this case the ICE is actually not as we know, are we just not using one form of energy (gas) to uphold and charge another form (electric)?? Please explain.
 

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With electric cars performance is diminished as state of charge is reduced. Your performance at 20% SOC will not be the same as 90% SOC.

Gasoline being used to charge the battery is no different than using grid power. 1 Gallon of gas is roughly equivalent to 34kWh. ICE is around 25-30% efficient so lets call it 8-10kWh back to the pack. Gasoline around here is about $2.40 a gallon so ~ 25-30 cents a kWh. Added bonus is you charge at the minimum 3x as fast as plugging in.

Being able to preserve battery miles and merely fill up instead of plugging in allows you to charge the battery at a rapid pace. An owner can use the miles when they want to, rather than having stealth "range anxiety." Make no doubt about it, this is a luxury item just like all of our products. To many having this capability is not minimal but a game changer with regards to the way they use their vehicle.

The Karma is by no means an economy vehicle it weighs >5300 lbs and consumes the most energy of any "EV" ever put into production (450-500 wh/mi on the highway). There is nothing economy about the vehicle from the solid sub-frame castings to the massive cast suspension knuckles to the 10 ton re-purposed truck bearings. Just because one drives in stealth mode does not mean that the vehicle is not consuming copious amounts of energy.
 

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Thanks. I am not convinced, but you do make some points about rapid charge, but the economics of filling up and charging versus electric charging are not clear to me. Well, the proof of the pudding is in the eating. If people are indeed buying your modules, they must be getting benefits out of them, so more power to you and to whomever is buying these modules. To an engineer like me, the benefit is still a mystery though. Thanks for the reply.
 

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It took me a long time to "get it", too, FiskerZee. Your statements above are perfectly correct in terms of the physics. So, it's really a question of philosophy. Do you want your Karma to be mostly an electric/emission-free car, or do you want your Karma able to operate at it's peak performance levels at all time?

The TOM unit allows you to keep your battery above 60% State Of Charge which is where the Karma accelerates the best (in SPORT mode). So, if you don't care about burning gas, and what you do care about is the best possible feel of acceleration pushing you back in your seat when you pass somebody on the highway, that's where the TOM unit shines. It keeps your battery charged ... at the cost of gasoline/emissions. The TOM unit gives you options to keep the generator turning more often than a stock Karma.

However, I would think a better battery would appeal to a lot us on the other end of the spectrum who drive our Karmas to maximize the electric range and aren't as focused on the G-Forces on our behinds.
 

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Finally, I go get it. thanks for the explanation JCMorrrill. Indeed, I get it when you explain in that way. I do very much agree with you though that the extended battery is much more appealing than running the ICE, which is against using an EV car in the first place. I don't want the ICE on at all if I can help it. A better battery would indeed be a great deal better than any TOM to allow ICE / EV operation at the same time for maximum acceleration. If I wanted that, I would have gotten a Tesla with the 3.5 seconds neck snapping feel. Thanks for getting this into my head. Now, I get it!!!!
 

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So.......

I'm 18 months and 12,000 trouble free miles into my Karma. I do not miss my Panamera Turbo a bit. But after reading and thinking of all the improvements that I would like on the car I have one that is most important.

I think increased electric range would be really fantastic. We only really get around 30 EV miles or so and I just love the novelty of it - I like how fun and quiet the car is to drive in EV mode - it is so different than anything I have driven.

So if we could double or triple the electric range that would be outstanding.
 

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We are building a few for ourselves and some enthusiast customers. Doubt there is much of a market to bring the cost down for the masses.

Most economical upgrade is getting some sort of NVH package. Two of our Karma's have it, and it makes a significant difference. Can barely tell that the ICE is on, under most circumstances.

Main places to add closed cell foam and butyl deadening are the frame rails, firewall, fenders, floors and tunnel, and area behind inverter close out panel.
 
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