MD-Tech PHEV Conversion Kit

There is a lot of confusion about who designed the Enginer PHEV kit and who owns the patents.

MD-Tech is a brand name owned by Shanghai Fountainhead Electronics, SFE.
The original idea for the PHEV kit is credited to Enginer. In the early years SFE and its Engineers did the research and development for the PHEV kit. The PHEV kit was supplied to Enginer which set itself up in Shanghai and then the US. Enginer do not hold any patents on the PHEV kit developed by SFE. MD-Tech have always had the kit on sale with a one year non-compete agreement for the US. This period is now over as Enginer have not bought kits from SFE for over a year. SFE lost their PHEV designer to Enginer but now that Enginer has gone out of business the PHEV designer is back at SFE.

SFE are working with Plug-in Autos UG out of Germany, for European distribution. The current status of the kit is, vehicle EMC testing is underway by TÜV labs in Shanghai.

There are many changes to the kit in the latest version and these may not be reflected in current documentation available. As soon as all the changes have been confirmed they will be posted here and on the Plug-in Autos website, http://www.plughybrid.de
I believe the above information to be correct, if anyone knows anything different please comment.

 

The kit puts out 1-20 amps, which is good for city driving a Prius averaging 30-35km/h. The Prius uses about 14 amps at 33km/h. You'll get an hour of driving at that speed on the 4kWh rated battery.

The reworked Kit has the E-Mark certification.
The new BMS (HW version 8.0, software version 1.0) data is up on PHEV kit System - Plug-in Autos
A couple of notes on the data: The graph shows single cell voltages against time. The PHEV kit was charged and plugged in at the start of the test, then bench tested at 210v 18 amps, then recharged.
Charge cut-off has been reduced for a single cell Hi 3.65v. Charging restarts if the Hi cell drops below 3.35v. The B1-B16 columns, (cells 1-16) in the data show active balancing with a "+" sign. Active balancing is on permanently.

It is tab delimited so save it, then import it with a spreadsheet app like Excel.
Here is the direct link to the data.
https://www.plughybrid.de/wp-content/uploads/2012/05/for_web_3x35V-recharger-test-data.txt

 

The Enginer V6 open architecture was adopted for overheating issues with the converter. Components have been changed in the MD-Tech converter to reduce waste heat losses and EMC noise. In Europe the climate is more temperate, converter heat protection shutdown is not as big an issue as it may be if you are living in a hot region. The open architecture has been discussed and it will be offered in the coming months. MD-Tech have version control for their changes now, so hardware, software and components are easily referenced. Labeling and version control should help users discuss any issues they find and discover resolutions quickly.

There are some legal issues if I relabel the kit. It may be useful to have one name for a worldwide presence. This eliminates much of the confusion about who is the manufacturer and helps to build MD-Tech's brand name. By setting up a contract with MD-Tech as a Sole Distributor for your region, you will have the ear of MD-Tech for any changes you need for the kit to work well in your region, if climate or layout is still an issue with the latest changes. The feedback loop for changes is very fast. They have the R&D Team and they have EMC, testing lab facilities at a big University. As you can see with the BMS data, things are going very well. We are getting around 88% efficiency for the system overall, (energy in vs. energy out).

 

Okay, please analyze the data, the pack balances quite well on average to within 0.05v for the difference between the Hi cell and the Lo cell.
Please refer to the BMS as MD-tech V1. BMS16D is a bifurcation Enginer had last year. There was split between Enginer and MD-Tech in 2011.

 

Correct. You should still see some decrease in fuel consumption. Starting the engine to help the topping up process will allow you to go back in to EV mode more often and for longer periods than without the kit. Every amp should save fuel.

 

If people can see the last 3 minutes of load, before LVC cut off, 75% of the pack is showing rapid voltage drops. This is an indication that the pack is at the bottom of its useful range. Keep in mind that the requirement of the BMS is to protect the battery cells from over discharge and over charge. This BMS fulfills these requirements. (BMS16D had problems with HVC set at 3.85V, over time the high cell, if not balanced would fail. ) By reducing HVC to 3.65V the margin for damage to the cell, due to any errors in accuracy or delay in cut off, are further reduced.

Another requirement of a BMS is to balance a pack. Enabling it to take a charge according to its specs and deliver that charge as a measurable output. The battery pack is rated at 4kWh. The useful energy coming out is around 3.85 kWh as can be calculated from the data. The BMS fulfills this requirement.

The BMS is doing its job.

BMS Display is "nice to have" and is useful for diagnostics. The BMS Display is not a requirement for operation of the BMS.

 

You would have to ask MD-Tech about ebay.com. I will be posting on ebay.de in March 2013 under username "Plug-in-Autos". You need a Distributor in the country (or economic area), that you are in to handle service and warranty. Similar to vehicle service warranty procedures, you need service warranty procedures and price lists for those repairs that can be claimed under the service warranty. If you are interested in becoming a Distributor please contact me and I can give you some pointers. There will be differences for the country that you are in, but a small business adviser or a government small business advice bureau should help you with the basic things that you need.