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Old 05-29-2016, 05:28 PM   #1
AccuXperT
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Join Date: Jul 2014
Location: Germany
Posts: 25
5 yr Member
Default My battery modification: Successful operation of a Segway with 94.4 V

Many years ago I purchased an i180 with deeply discharged Li-Ion-batteries. Rather than simply new batteries to buy I opened the defective batteries and made me detail the electronics (BMS) and the lithium cells used familiar. I have measured every detail and found that I can also use alternative types instead of the original VALENCE cells.

Below I describe how I operate the Segway with 94.4 Vdc without an error message!

As part of this development work I have increased by incorporation of a higher number of cells the sum voltage. The aim was to find out what can be operated with maximum number of cells of the Segway, to achieve a gain in range. The basic idea is sinking of the motor current by a higher battery-voltage, whereby the overall efficiency increases and the possible range becomes larger.
At this time was the condition that all of the cells must fit into the battery case and the BMS-electronics and the Segway-Base accept this change.

For this it must be mentioned that the regularly usable voltage range of the Li-Ion-battery is about 60V to 82V. In order to realize a higher voltage, the BMS electronics must be modified in some places. These changes I have made in my e-lab, this maybe I'll discuss later in more detail on it.

So I was able to realize battery voltages above 82V, the Gen1 then proceeds without error but at 5 km/h reduced with neutral face, until as the voltage at the battery terminals is again below 82V.

The (converted) BMS has seen thanks to automatically switchable voltage minimizer only 80V - not the fully 94,4V. Unfortunately, the Gen1 Base has the dizziness noticed (battery-terminal voltage to high), the Segway but went anyway at 5 km/h with Neutral face.

The possible reason that the (Gen1-) Base has ever accepted the high voltage of 94,4V, could lie in the fact that the internal ADC of the base is already running on the top converter limit, because the ADC was not dimensioned for such high voltages.
Incidentally: A original battery with indeed more than 94V terminal voltage is likely to be short of the smoke ...

The range of the i180, incidentally, was even higher, estimated (never fully tested) than 65 km ...!

Conclusion: I run my own batteries, which I have developed even for several years. These batteries run with me stable on an i180 (V14.1) and an XT (V14.2). Although over 82V to operate goes but does not make sense, because the Segway ride at 5 km/h limited with the neutral face. A reasonable operating with more than 82V will therefore unfortunately not prevail.

-> Photos from the successful test run with 94,4V :

Akku-Umbau beim i180, Fluke-DVM zeigt 94,4V am Segway-Akku, kleines Download.jpg

Akku-Umbau beim i180, Wattmeter zeigt 94,32V - Kleines Download.jpg

-> Here the video for the successful test run with battery overvoltage: Test drive in the study with "only" 94,4V. With fully charged cells, the battery terminal voltage would be gigantic 97,0V - that was me then but a little too much for the i180 ...
(the sound is unfortunately in German but the description of the video is in 2 languages)​​ :




Safety Notice: Modification, reconstruction and operation of alternative Segway-batteries require some background knowledge, so that the benefit is set also in the longer term. The above presented developments I have done for me and does not represent a recommendation to imitate. High voltages and CMOS electronics require some knowledge and the user should absolutely know what he is doing here.
Safety for man and machine and the Segway integrity should be the top priority !
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