Tag Archives: BMW i3

Charged EVs Covers Munro’s BMW i3 Report for $10

Charged EV Covers Munros $10 BMW i3 Report

Charged EVs Covers Munro’s BMW i3 Report for $10

Never a person to shy away from taking an action to shake up the market, Sandy Munro started to offer Munro & Associates BMW i3 Report which consists of 10 Vehicle Zones and almost 24,000 pages of in-depth analysis (a must have for EV enthusiasts), is now getting picked up by some of the media, including Charged EV Magazine.

For their full article on this, click here:  https://chargedevs.com/newswire/sandy-munro-offers-bmw-i3-teardown-report-for-10/

This report cost Munro over $2 million dollars to create and was sold for $89,000 up until recently, showcases the Munro benchmarking prowess and offers to the EV enthusiast or the engineering grad student alike a view into one of the most groundbreaking EV for its time!

As an homage to one of Sandy’s former mentors, Sandy wanted to cut a break for the average Joe who cannot afford an industry priced report, but maybe has the inkling to be an entrepreneur in the EV world, maybe even the next Elon Musk.

Chances to view a report like this for this level of price are unheard of in the industry, so we encourage you to take advantage of the opportunity now before we remove the report forever.  If you are interested, click on this link here to take you to the report purchasing page:  https://munrolive.com/support-%2F-store/ols/products/bmw-i3-reports


Munro Offers BMW i3 Teardown Report to Public for $10

BMW i3 $10 Report

How do you inspire and help the next Elon Musk in creating the next breakthrough electric vehicle?

If you’re Sandy Munro, CEO of teardown benchmarking and product design firm Munro & Associates, you offer your landmark BMW i3 benchmarking analysis report – a detailed 23,000+ page document that usually sells for $89,000 – for only $10. That’s just $1 per vehicle zone: body; exterior; rolling chassis; battery system; electronics; cooling; driveline and motor; ReX system; IP and interior trim; and seats.

To put this into perspective, it cost Munro over $2 million to develop this in-depth report that analyzes more than 54,000 parts. Most of the OEM’s in the world have purchased it. All the parts are documented with materials, weights, cost, fasteners, glues, suppliers for components and more.

Check out this video where Sandy discusses the report and its potential to inspire: https://www.youtube.com/watch?v=OCDamRUFHYs

Here’s a direct link to purchase the report: https://munrolive.com/support-%2F-store/ols/categories/bmw-i3-reports



Model Y Series: Episode 20: Noise, Vibration & Harshness Countermeasures, Cooling Pack & AGS

Episode 20: Noise, Vibration & Harshness Countermeasures, Cooling Pack & AGS

Welcome back to episode 20 of Munro’s Tesla Model Y Performance teardown, where Munro & Associates CEO Sandy Munro walks viewers through the various types of noise, vibration and harshness (NVH) countermeasures found in the vehicle.

There are various NVH countermeasures present on the Model Y, including: lofted fiberglass; foam-in-place PUR (polyurethane) with TPO (thermoplastic olefin) skin; a pumpable sound deadener; mastic patches; and die-cut foam.

Sandy also gives an overview of the construction of the cooling pack that’s outside of the vehicle, as well as the active grille shutter (AGS) system.

To end the segment, Sandy shares more about what Munro is all about and what they do, including analyzing products, such as the most extensive study Munro has ever done on the BMW i3, and helping companies design better products.

You can see the full details on the NVH countermeasures, cooling pack and AGS system here.

Interested in more? Visit www.MunroLive.com for full details about Munro’s Tesla Model Y discovery process. This site will offer regular insight from Sandy, interactive data and reports, and livestream from Munro’s headquarters.

Also, please consider Sandy’s suggestion for how to pay it forward during these challenging times. Together we have the ability to make a difference!

Tearing Down Tesla Segment 8: Comparing the Cooling Strategy / Housings of Motors for Tesla Model 3 vs BMW i3

Both the Tesla Model 3 and BMW i3 have novel approaches to cooling the motor. This week’s segment compares these approaches. Let’s get to it.


The BMW i3 uses a two-piece motor housing to allow for large coolant channels in the housing walls to cool the housing, which in turn cools the motor and stator laminate stack. The Tesla Model 3 has a coolant to oil heat exchanger on the exterior of the housing and uses the oil to flow through grooves and channels in the stator laminate stack to cool the motor.

The advantage of the BMW i3 design is that it eliminates the need for a heat exchanger, along with the thermal transfer loss between the two fluids. However, the two-part housing requires more processing costs related to casting and machining a second housing component.

The advantage of the Tesla Model 3 design is that it only requires one housing and allows for direct cooling of the stator through contact with the cooling fluid (versus through a housing wall). However, this design requires a heat exchanger assembly and an oil pump to circulate the fluid. These two commodities add significant cost to the motor assembly, but they also have a dual purpose of providing heat to the battery as well as cooling the motor. In this design, the systems pays for some additional functionality.


The general conclusion is that Tesla is increasing their cooling performance of the motor by running oil directly through the laminates, but accommodating this system requires a cost increase for added commodities of a heat exchanger and pump. This drives approximately a $31 cost increase on the Tesla Model 3 versus the BMW i3 design, even though the Tesla was able to use a single piece housing.


Each of the motor housings and companion cooling components were analyzed in Design Profit to understand the full cost of cooling the motor. Specifically, the housing full fabrication process was captured in the software, including the casting and all machining operations.

Tearing Down Tesla Segment 7: HVAC Differences in the Tesla Model 3 & BMW i3

There’s a rather traditional design tradeoff for the IP HVAC ducts in the Tesla Model 3 and the BMW i3. Read on to learn more!


The BMW i3 uses blow-molded ducting, which can reduce material weight and cost by allowing for thinner walls on the duct, but often requires multiple pieces to create the path to route the air. The Tesla Model 3 uses a three-wall injection molded duct, which reduces material weight and cost by eliminating one side of the duct and using the instrument panel substrate for that wall. This design often integrates several pieces into one part and requires more design work and a rather large specialty assembly jig to weld the part to the instrument panel.

Second, the BMW i3 has rather traditional air vents. There are four vent assemblies (two on each side of the driver and passenger) and each vent consists of several small parts assembled to allow for manual control of the air side-to-side and up and down. The Tesla also attempts to reduce cost using a very novel approach to controlling airflow at the vents. Tesla uses a patented air vent design that uses two opposed air streams to control airflow allowing for the need of only two vent assemblies with fewer vent components, as less directional fins are required to focus the air. To further improve the design, they motorized the control (via a touchscreen) to add an additional level of functionality. With this design, they were able to reduce that cost of the components by making it fewer parts, but then put that cost back into the system by adding functionality.

It is interesting to note that Tesla is possibly able to adapt this specialty design with a more complex assembly jig because its vehicle production volume is significantly higher than the BMW i3, which allows those engineering and tooling costs to be distributed across more parts, allowing for bigger development budgets.

Tearing Down Tesla Segment 5: Seat Comparison on Tesla Model 3, BMW i3 and Chevy Bolt

Seats are another example of how OEMs spend money in different areas. For example:

  • The Tesla Model 3 only uses vinyl for its front seat covers; while
  • The BMW i3 uses high-end leather and cloth; whereas
  • The Chevy Bolt uses leather and vinyl.

Background: This shows that BMW and Chevy prioritize the quality and feel of the seat surface, while Tesla focuses more on adding functionality with a 12-way seat control (versus the manual adjustments on the i3 and Bolt.)

Typically, an electric vehicle is competing alongside luxury vehicles, which normally expect powered seats, but often many electric vehicles will revert to a manual seat in order to reduce the weight associated to the heavy motors that provide actuation.

Data: The front seats for: Model 3 are $568 and 44.8kg; versus the BMW i3 at $729 and 39.8kg; versus the Bolt at $532 and 38.3kg.

Methodology: During the teardown process of each vehicle, we fully disassembled the seat to analyze the covers, structure and electromechanical mechanisms. Each manufacturing process to sew, weld or stamp the components for the various areas of the seats were quantified to develop a full cost for the seat.

Tearing Down Tesla Segment 4: Battery Cooling System Comparison on Tesla Model 3 vs. BMW i3

The Munro engineering team also spent some time analyzing the battery cooling systems for Tesla (coolant) and the BMW i3 (AC fluid).

Background: Outside of the battery pack, the primary cost difference seen between the Tesla Model 3 and BMW i3 is the cooling system. The Model 3 (similar to other coolant cooled battery packs, such as the Bolt) requires an auxiliary water pump to push coolant through the battery cooling circuit. Since the BMW i3, which uses AC fluid, has to move much less fluid, the compressor does not require an additional pumping mechanism, but may require a slight upsizing of the AC compressor to compensate for increased demand.

Further, an added benefit that the Tesla battery pack cooling gives to its functionality is that each battery cell in the pack has full contact along the side of the coolant tube. This differs from the BMW (and the Bolt), which have only module level contact to the coolant system (at the bottom of the battery module). This enables the Model 3’s cells to cool more evenly, as well as more efficient control of pack temperatures.

Data: Within the battery pack, the Tesla cooling system costs approx. $270 for a 75 kWh pack, which translates to $3.60/kWh in cooling cost vs. the BMW, which costs approximately $84 for a 22 kWh pack translating to $3.80/kWh. 

Methodology: All coolant system components were removed from the vehicles. Install to vehicle and battery pack were captured in Design Profit to develop assembly costs. Next, the fabrication of each part within the cooling racks in each battery pack was analyzed to develop cost for the parts. These costs are then totaled and analyzed via Design Profit to better understand the differences between the vehicles.

Tearing Down Tesla Segment 2: Tesla Model 3 vs. BMW i3 with REx System

What costs more? An electric vehicle with an extended range system or a full electric vehicle? How does OEM assembly time factor in?

Background: The supplier component costs for a full battery electric vehicle, like the Tesla Model 3, are often more expensive than an electric vehicle with a range extender, like the BMW i3. However, for the OEM, an electric vehicle with a range extender (or any type of hybrid vehicle) will drive more OEM assembly costs. Additional assembly workstations are required to build a range extender system (often in a spur line), then more stations must be added to the main final assembly line in the vehicle assembly plant.

Side note: this does not include the cost to assemble the engine, which could be supplier or OEM assembly costs.

Data: The BMW i3 REx system can be estimated to drive approximately $45.61 in OEM assembly costs for installation and assembly of the system components into the REx module. This drives the need for approximately 35-40 more workstations in the assembly plant.

Methodology: Munro’s Design Profit® software has a built-in scoring system that allows users to analyze handling and interaction times when assembling parts. Munro uses this scoring system, along with a library of industry standard fastening and operation times, to generate an estimated time and motion study for the assembled parts and work cells that are required. Then, in order to generate assembly costs, that assembly time is matched with a work cell rate for the require operator and equipment.

Tearing Down Tesla: Comparing Secrets of Tesla and Other Leading EVs

Calling all automotive engineers looking for objective technical information about today’s leading electric vehicles (EVs).

This post kicks off a series of articles that will compare notable aspects of leading EVs. From OEM assembly time to suspension and from battery cooling systems to HVAC ducting and venting, this series will cover a lot of ground. Most importantly, it aims to offer knowledge that’s interesting and valuable to today’s engineers … with data points that support our findings.

We used our proprietary Design Profit software for all of our teardown analysis. It enables the teardown team to document each part, how it is installed in the vehicle, as well as how it’s assembled in each subassembly. With this data, we’re able to reverse engineer the assembly process for the given vehicle. More information about the software can be found here: https://designprofit.com/

With that said, here’s the first post ….

Did you know that the BMW i3 has a serviceable battery pack while the Tesla Model 3 doesn’t?

Background: The BMW i3 has a serviceable battery that can be lowered from the vehicle by removing the pack’s mount bolts located on the exterior of vehicle. Individual sub-packs can be replaced after removal of the cover and sub-pack fasteners.

The Tesla Model 3 battery pack was designed not to be serviced. It requires the removal of bolts in the interior and exterior of the vehicle to drop out the battery pack, as well as the removal of the vehicle’s seats and carpeting (to access bolts). The battery pack uses structural adhesives to seal and mount its cover and sub-packs, which does not allow service to open and easily remove modules for repair.

Insight: The advantage of the Tesla Model 3 non-serviceable battery pack is that it reduces the final assembly cost of the battery pack. The disadvantage is that if significant cell damage happens in the pack, then it requires a full swap of the battery pack.

Side note: based on the range for the Tesla Model 3 battery pack vs the BMW i3, in order to equalize, the BMW i3 assembly costs would be considerably higher than the current cost analysis.

Data:  The Tesla Model 3 uses three lines of structure adhesive bead and 78 fasteners, with a final assembly cost of $36.87 to mount the sub-packs and install the battery pack cover. The BMW i3 battery pack uses 120 fasteners, with a final assembly cost of $41.39.

Sandy Munro Shares Thoughts on Structural Adhesives in Automotive Engineering Article

In the recent Automotive Engineering article “Stuck on Structural Adhesives” from Automotive Engineering, Munro & Associates CEO Sandy Munro shares “We’ve used adhesives forever. It’s just that the amount of confidence in them has drastically changed [in recent years].”

According to the article, as the need for lighter materials and enhanced body performance intensifies, structural adhesives are flourishing as a materials-joining solution. The widening reliance on high- and ultrahigh-strength steels and aluminum for body structures, particularly unitized bodies-in-white (BIW), to cut weight without sacrificing crash-mitigating strength or handling degrading rigidity, is the prime factor driving the expanding use of structural adhesives.

Sandy references his firm’s findings from the BMW i3 teardown and adds, “Anything you can possibly imagine, they glued together. The polyurethanes they are using are unreal.”

To read the full article, visit: http://bit.ly/2pHYsRS.