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Fiat Scudo Range Extender - cemtec.dk

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<strong>Fiat</strong> <strong>Scudo</strong> <strong>Range</strong><br />

<strong>Extender</strong><br />

Project Conclusions


Table of Contents<br />

List of Figures...........................................................................................................................i<br />

1. Project Mission .............................................................................................................................. 1<br />

2. General Information ..................................................................................................................... 1<br />

3. System Design ............................................................................................................................... 2<br />

4. Testing ........................................................................................................................................... 3<br />

5. Final Conclusions ........................................................................................................................... 5


List of Figures<br />

Figure 1: <strong>Fiat</strong> <strong>Scudo</strong> Van ............................................................................................................................ 1<br />

Figure 2: <strong>Range</strong> <strong>Extender</strong> .......................................................................................................................... 3<br />

Figure 3: Real Time Pack Voltage .............................................................................................................. 4<br />

CEMTEC – Majsmarken 1 – 9500 Hobro – Denmark Tlf +45 96 40 15 00 i<br />

Project Conclusions


1. Project Mission<br />

The purpose of this project was to develop, test and demonstrate a compact, methanol fueled,<br />

HTPEM module for use in automotive applications.<br />

The module acts as a charging system to increase the range of an electric vehicle. The prototype<br />

system was featured inside an electric <strong>Fiat</strong> <strong>Scudo</strong> van converted by Enerblu, an example of which is<br />

shown below in Figure 1. The goal was to increase the range of this electric vehicle from 150km to<br />

over 500km and to provide a robust solution capable of surviving a three month road test program.<br />

2. General Information<br />

Figure 1: <strong>Fiat</strong> <strong>Scudo</strong> Van<br />

With almost two million vehicles on the road in Denmark, there is a large potential market for electric<br />

vehicles. Gas prices, registration tax and road use taxes in Denmark are some of the highest in the<br />

world. As a result of the current tax break given to electric cars, the market will shift in this direction<br />

in the future given appropriate cost effective solutions.<br />

The prototype system for this project will feature an integrated methanol reformer to produce<br />

hydrogen as needed. This design feature avoids all of the potential hazards related to storing and<br />

fueling high pressure hydrogen tanks. The following reaction takes place inside the reformer to<br />

produce hydrogen.<br />

CH3OH + H2O � 3H2 + CO2<br />

CEMTEC – Majsmarken 1 – 9500 Hobro – Denmark Tlf +45 96 40 15 00 1<br />

Project Conclusions


There are many advantages to using a renewable resource such as methanol to produce hydrogen.<br />

Several are listed below.<br />

- Methanol is fully biodegradable<br />

- Methanol can be reformed into hydrogen at low temperatures allowing low heat losses and<br />

rapid start up<br />

- Methanol is a renewable energy carrier and can be created using wind power in combination<br />

with biomass and waste products<br />

- Methanol is a liquid at room temperature and can be distributed like diesel or gasoline<br />

- Methanol is traded all over the world so it is accessible and cheap<br />

3. System Design<br />

The system was assembled inside a custom aluminum shell and included the following components<br />

- 2 X Serenus 390 Series HTPEM modules<br />

- 2 X prototype methanol reformers<br />

- 100L integrated fuel tank with fuel pumps<br />

- DC power supply<br />

- Integrated fire suppression system<br />

- Integrated control board with safety shut down<br />

- Protective shielding<br />

The fully assembled range extender system without protective shielding is shown below in Figure 2<br />

prior to installation in the <strong>Fiat</strong> <strong>Scudo</strong>.<br />

CEMTEC – Majsmarken 1 – 9500 Hobro – Denmark Tlf +45 96 40 15 00 2<br />

Project Conclusions


Figure 2: <strong>Range</strong> <strong>Extender</strong><br />

The system was designed so that a fork truck could load the system into the back of the van with<br />

minimal effort. To complete the installation, exhaust and intake air paths were added as well as<br />

connections to the battery and BMS. This design meets the fully integrated ‘black box’ design<br />

requirement requested. In future revisions, the system could be further reduced in volume.<br />

4. Testing<br />

The entire system was tested in the laboratory prior to installation in the <strong>Fiat</strong> <strong>Scudo</strong>. From lessons<br />

learned throughout this process, several changes were made to the prototype system. These changes<br />

increased the durability and efficiency of the system while reducing start-up time. Lab testing allowed<br />

for the development of a more robust control system which helped implementation considerably.<br />

Using the cell voltage information supplied by the BMS, Serenergy was able to construct a control<br />

system and successfully charge the battery while the van was parked. A system of relays and safety<br />

checks were implemented to ensure a safe environment was maintained both for the battery pack<br />

and vehicle occupants.<br />

Once the steady state charging milestone was achieved, efforts were focused on charging while<br />

driving. When the car was received at Serenergy, there were still many unknowns. The most crucial<br />

CEMTEC – Majsmarken 1 – 9500 Hobro – Denmark Tlf +45 96 40 15 00 3<br />

Project Conclusions


information missing was related to the battery cells. Too many assumptions were made regarding the<br />

performance of the cells.<br />

When test driving the <strong>Fiat</strong>, large (>40V) pack voltage swings were noticed prior to implementing the<br />

fuel cell system. While some voltage fluctuation (≈20V) was expected and planned for, the large<br />

fluctuations were unexpected. Further examination was required so real time battery data was logged<br />

on a 60km road trip. The data was plotted and the results are shown in Figure 3.<br />

Voltage<br />

300<br />

280<br />

260<br />

240<br />

220<br />

200<br />

180<br />

Drive Cycle - Battery Only<br />

700 1700 2700 3700 4700 5700 6700<br />

Time (s)<br />

Figure 3: Real Time Pack Voltage<br />

While the drive cycle does not lend itself to a constant rate of discharge, the resulting pack voltage<br />

fluctuations were higher than previously assumed. The original integration plan called for the fuel cell<br />

system and battery pack to be directly coupled to eliminate the efficiency losses, cost and complexity<br />

of DC/DC converters. This plan had to be re-examined as near instantaneous 40 to 50V voltage<br />

fluctuations are unacceptable when operating an integrated fuel cell/reformer system. These<br />

fluctuations result in fuel starvation in the fuel cells or massive temperature spikes in the reformer<br />

depending on whether the voltage increases or decreases.<br />

CEMTEC – Majsmarken 1 – 9500 Hobro – Denmark Tlf +45 96 40 15 00 4<br />

Project Conclusions<br />

voltage


Several solutions were suggested at this point.<br />

1. Integrate a DC/DC converter with high frequency pack voltage measurement<br />

This solution would allow the fuel cells to operate at a constant load at all times. Currently there is<br />

no way of transmitting a high frequency pack voltage reading accurate enough to control the<br />

DC/DC converter. Software to allow for this is currently in development at Lithium Balance.<br />

2. DC/AC converter through the charger<br />

This solution is less efficient as it adds another conversion between pack and the fuel cells. In this<br />

case, the power would be transmitted first through the DC/AC converter and then through the<br />

charger. If these losses are acceptable, this solution could potentially be the quickest to<br />

implement.<br />

3. Upgrade the battery pack<br />

The ideal solution in order to test whether a system can be created that operates efficiently while<br />

directly connected to the battery pack would involve upgrading the cells. By using a higher quality<br />

cell, the voltage fluctuations would be minimized. This is the ultimate goal however may not be<br />

cost effective for a commercial system.<br />

While these are all potentially valid solutions, all will cost a considerable amount of money to test and<br />

implement. This development was not budgeted for as it was expected the cells would be of a higher<br />

quality. As a result, these options will have to be explored in a separate study starting January 2010.<br />

5. Final Conclusions<br />

While there are many areas to improve upon moving forward, the following milestones were<br />

successfully achieved. Serenergy was:<br />

- Successful in combining fuel cells with a new prototype reformer<br />

- Successful in charging the <strong>Fiat</strong> <strong>Scudo</strong> battery while parked<br />

- Successful in packaging system within the constraints of the <strong>Fiat</strong> <strong>Scudo</strong><br />

- Able to provide a proof of concept in a lightweight mobile package (Black Box)<br />

CEMTEC – Majsmarken 1 – 9500 Hobro – Denmark Tlf +45 96 40 15 00 5<br />

Project Conclusions


With further investment in this project, all of the remaining issues can be solved and a more robust<br />

system can be road tested.<br />

CEMTEC – Majsmarken 1 – 9500 Hobro – Denmark Tlf +45 96 40 15 00 6<br />

Project Conclusions

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