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 ... :eek:

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 :

Attachment 2432

Attachment 2433

-> 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)​​ :

https://www.youtube.com/watch?v=6Y8fbCz9L-U


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 !
.

Hi,

I am in the process of remanufacturing the nimh bms boards.

on my journey I have had my i180 running from lead acid batteries and my own cpu board giving the base the correct data.

so it is possible to run old segway on any battery! as long as voltage is correct.

Great work on the battery modifications!

regards

Ian

Battery-Modification on Gen1
 

Yes exactly!

My report of the operation a Segway with 94,4V should show that it works! I have my i180 even operated only with a 70V power supply, completely WITHOUT batteries / cells. However, with Li-ion PCBs the Rev. AC and AF.
I've never tested the older NiMH-PCB but I think that this can be manipulated more easily.
Maybe the security questions are not as sharp, such as the scanning of the individual cells / cluster like the Li-Ion BMS does.

dorrington, I wish you continued success!

If you want you can post a few pictures here of your battery-conversion - would be happy ...

I think it's to much voltage :eek:

Maximum Battery-Voltage
 

Absolute!

I wanted only to show what the Gen1 Segway at maximum voltage accepted - it is borderline.
About 82V battery voltage the Gen1-Segway reduces the speed to 5 km/h. So driving course makes no fun ... Therefore voltages above 82V are at battery self-construction projects to avoid. Even when it comes (and an even greater range produced) it does not make sense to go over 82V.

Whoever builds his battery itself should consider these 82V-Limit.

After many long hours.....
http://forums.segwaychat.org/attachm...1&d=1467071082

The story so far....

https://youtu.be/7C1JEm17GZc

Regards

Ian

Great work the pair of you! The elephant in the room for Segway running costs has always been the cost of batteries. A full understanding of how they work is the first step in solving this.

If battery packs (that have been cared for) are expected to last about 8 years with regular use, I guess it would be about $200/year. Not horrible but not cheap, either. I'm guessing the cost of the electricity used for the life span would be less than that. Between batteries and the cost of the machine, Segways aren't the cheapest vehicles out there. Still, I think their quality and versatility makes them worth every penny. By far and away the favorite of my vehicles.

Ions82,

I totally agree, however, living in the UK makes it very hard to get cost effective batteries, even more so when they are twice the price I paid for the Segway itself...😊

Thank you for looking,

Ian

You must be charging your batteries with magic electrons if they last 8 years! I never got more than about 40 months before they were so degraded they were not really useable, especially in cold weather. Of course, it could be that recent batteries are significantly better than the ones produced say 5 years ago. My segways were always used for commuting, which was use on the road as an electric bicycle- slightly grey area in the uk but definitely less grey than trying to ride on the pavement where you would not get further than the first policeman without being stopped and charged, so most use at 12 mph. The Lithium batteries were definitely less durable than the NiMH batteries, in my experience, though they obviously had much lower capacity. At one point Segway sent out a questionnaire, trying to establish the sweetspot for preferred range and charging rate- do you want a battery that takes two days to charge and has a range of 30 miles, or one with a range of 10 miles and charge time of two hours. I don't think they saw a sufficiently clear pattern in the responses because the batteries were never changed.

[QUOTE=AccuXperT;239454]Yes exactly!

can u make a non lithium battery that will replace at least temporarily the two lithiums on an X2 so us disabled folks can take our segways on airlines? reguardless of price i think many of us could use something like this
i certainly could im an old disabled veteranandstroke survivor
that cant sit in a wheelchairit hurts my back too muchto traveling with my own modified seg is a dream

I have one 2006 battery, one 2007 and one 2008 and I can put any two of them on an I2 and go more than 15 miles. I have read about people who have gone 10 years and 10,000 miles on one set of batteries - Don't know for a fact that this is possible, but I know my three 'old' batteries are still in remarkably good shape for their age

Don

Hi Rotorblades,

I am working on a NIMH battery with lithium data but it won't be a quick process, I have a lot of data to collect, I am hoping AccuXpert or someone else can shorten my journey!. I also need to prove the safety of my charging protocol, although, NIMH batteries are alot more stable than other types.

I am hoping to reprogram the existing NIMH bms without having to open the case..

I'll keep you posted.

Regards,

Ian

I'm at 9 years and 9000 miles. Batteries still going well, but substantial range has been lost. On the golf course, when new, I could easily play 36 holes on a hilly course with 2 bars charge remaining. This year I could make only 18 holes with 2 bars, sometimes 1 bar remaining - and when it got cold this fall (45-50 degrees) could barely go 16 holes on a hilly course, 18 holes on a flat course. Similar results on pavement; batteries seem to be down about half from the original performance. I'm about ready to do a battery upgrade.

9 years
 

9 years, and 9,000 miles. What year were your batts manfactured?

Sorry to bump an old post - I can't find what I need on the forum, Do you have any info on the mini plus BMS? I need to check the status of the cells. I have an arduino I could use to pull data if necessary

tia, Rich

Battery
 

HI RICH,

All I can say is that the gen 1 and 2 segway use i2c as the communication protocol..both generations are slightly different though.

I don't know about the minis....time to experiment..

Good luck

Infos about the circuit of the batteries needed
 

Hi, I hope somebody answers.

I have 2 segways gen1 that are almost completely new. I got them with burned chargers which i fixed successfully in the course of 3.5years of work. I also received them without keys and I successfully managed to create and program new ones. So now we arrive to the point of the battery. I have 2 batteries rev AB and rev AC. I also bought two extra dead batteries rev AF but the don't work properly. So let's stick to AB and AC.
In both of them I have installed new cells. The AB worked out of the "box". The AC had a diode in DC/DC converter burned and after replacing it managed to make the segway run. BUT I still have some issues.
The AC cannot charge from the internal charger. The mosfet that is after the diode from the charging pin never gets activated. Mosfet is fine, it just never get's the 5V signal on it's base so it never allows the current to flow from the charger. I have spent several days trying to find what is burned but I can't.
Regarding AB is charging but voltage on the cells go very high up to 86V so i'm not sure if this is the correct behavior or there is another issue there too. Both batteries looks like doing balancing correctly, but I see that if I leave them one day on the shelf the discharge too much, probably because they try to make balancing which burns energy. So I have no clue how a correct battery should behave, I don't have any healty batteries here. My questions are the following:

1. What is the maximum voltage the charger should leave to the batteries when the charging process is complete?
2. Where are the 5V generated in AB/AC revision board
3. Which circuits control the charging mosfet?
4. What happens if we bridge the two batteries together during run? I'm considering charging them as one, or even with external chargers