S646se - Full LITHIUM Pack Project - First Attempt

[Burgerman]

Wouldnt it be good if all chairs had this much range?

My 45V chair, (and my new green chair) both have about 8 miles more range than yours even.

Because one is 45V and that increases efficiency in spite of the 16mph thing, and means its huge 3.24 kwh battery is more than equal to the 120Ah green chair.

And that green chair still has 120Ah x 25.6V (or 3.1kwh of energy), and battery freindly 6.2mph motors... That should get better than 2.28 Ah per mile and it uses low rolling resistance radial pneumatic tyres too. Even ignoring all of that, and using your own data of 2. 28 Ah per mile gives 120Ah div by 2.28 = a crazy 53 miles... Or 8.83 hours of full speed 6mph non stop driving.

[expresso]

yeah thats great - and they all should have this range period - i really dont think i can get them down low enough to have a LOW CELL - i mean yeah i can if i really try to do it -- but under normal usage - even with my long trips i take - i cant get it that low -

i am going to try to use 30 or 35 miles just to see where that leaves me - but its not something i will be doing daily - - i can easily make it to Yankee stadium - - Bronx - Queens - Brooklyn - using the bridges - thats pretty good -
but this one bridge was the one i wanted to do since i always seen it from a distance and as i got closer with each ride i took - i realized it was do able -

theres another bridge - not sure if i can make that one - into Staten island - that might be out of reach - i have to look into that - but i have to say - this one into NJ - was very high - i was a bit concerned - afraid of height really - the side rails seemed rusty and shaking as traffic went by - makes you wonder -

[expresso]

Wouldnt it be good if all chairs had this much range?

My 45V chair, (and my new green chair) both have about 8 miles more range than yours even.

Because one is 45V and that increases efficiency in spite of the 16mph thing, and means its huge 3.24 kwh battery is more than equal to the 120Ah green chair.

And that green chair still has 120Ah x 25.6V (or 3.1kwh of energy), and battery freindly 6.2mph motors... That should get better than 2.28 Ah per mile and it uses low rolling resistance radial pneumatic tyres too. Even ignoring all of that, and using your own data of 2. 28 Ah per mile gives 120Ah div by 2.28 = a crazy 53 miles... Or 8.83 hours of full speed 6mph non stop driving.

i did 4 hours non stop - and it was a trip - but got to say - since using my new chair - its so much better over the roads etc, - that i dont feel so broken banged up after the ride - with the ADD ON chair - alot harder ride - that one would make you feel banged up when done - its fun to ride - but wears you out more for sure -

if i added the ADD ON - would bring me to 140ah pack - another 15 miles added to my range - yeah once you cross over into lithium - cant go back to LEAD -

[Burgerman]

141 Ah div by your 2.28Ah per mile means 61.82 real world measured mile range. So 55 should be safe to attempt.

Thats not the imaginary bulshit ISO claimed range you see advertised for lead chairs, which we know is garbage but a real measurement in use on the street and achievable in practice. When I first told people about these figures nobody believed it.

[expresso]

right - no one believes me either - only the few that really know me and helped me build it - i have to show everyone the pictures on my phone to show them what i did and whats in the chair etc, - to be honest - i wont believe it either if someone just says that - i would have to look into it myself - most of them wont -

i do have a few who find it more interesting - i know a few who use the manual chairs with built in lithium on the Wheels - -another person she has the small pack you add in the middle of the manual wheelchair in the rear - she has a wrist band on one hand and controls it from that - pretty cool for manuals - it makes it alot easier for them when using it for a long time etc,

when shes in college etc, -

i am glad i was able to fit the 105ah pack as compared to what i was going to do 90ah - if that didnt fit - every bit helps - i dont even think i need to use the ADD ON with the Full pack chair - i cant even drain that alone - i have to try to use it more longer just to see how much i can do and what level the cells are - just so i have an idea

i would have to be ready for that day - start early -

[LROBBINS]

The Verrazano Narrows Bridge is really beautiful. If it actually has a walkway, I hope you decide that you can make it there, but if it doesn't have a walkway don't you dare try to mix with auto traffic! Take the bridge one way from Brooklyn to SI, and then the ferry back to Manhattan.

[expresso]

yeah i remember driving over there to visit my sister there - i did use the ferry once with my Car - i have to see - that may be too much to attempt - if i see it can be done - i would only try that if it has a walkway for real - i am not crazy about taking the ferry back though - i didnt like it then with the Car - it was quicker though -

nice day today but windy - getting ready to take a short ride with my friend - will be easy day - hes got LEAD - so i know i cant wear my chair down today -

[Burgerman]

10.5 Low Voltage Cut-out, Low Voltage Time
These two parameters allow a low battery voltage cut-out function to be programmed. Such a function can be used to prevent
over-discharge of the batteries.
If the battery voltage is below the value set by Low Voltage Cut-out for a period of time longer than that set by Low Voltage Time,
then drive will be prevented. This will be recorded in the Power Module’s error log.
Drive will then be permitted to resume when the battery voltage rises above the value of Low Voltage Cut-out.
The programmable range for Low Voltage Cut-out is 16V to 22V in steps of 0.5V.
The programmable range for Low Voltage Time is 1s to 255s in steps of 1s.

From the r-net programming guide.

So you can set it to 22V (preferred) which is 2.75V per cell to safeguard your battery.
Or 21V for 2.625V per cell if you prefer. It will do the same as the BMS and stop you from over discharging.

[expresso]

Hey you know i didnt think of that - your right - the Rnet does have a Volt cut off - i think its set at 18V - thats 9V per battery - when there was LEAD - i can set that to 22V and thats it - that would save the battery in the event - but the chair would stop working -

but by then it would be 40 miles i think - and i doubt i will do that many anyway - i will leave the voltage time - and just change the Cut off from 18V to 22V - should be fine ? then when i get a good day and decided to test a 30 miles ride or 35 just to see where that leaves the Cells-

R net = built in BMS

[Burgerman]

Yes, as I said a BMS isnt required in a properly implemented system. All its "jobs" are done more efficiently and correctly by careful cell choice, built in current limiting inthe controller and low voltage cut off. And a real charging system.

[expresso]

Yes, as I said a BMS isnt required in a properly implemented system. All its "jobs" are done more efficiently and correctly by careful cell choice, built in current limiting inthe controller and low voltage cut off. And a real charging system.

pretty cool - so this can actually be done by the manufacturers - the same way really - everything is taken care of - the chair is fused already - i think my chair comes with a 80A or 100A built in already - so no need to do anything -

the only thing they have to do is change chargers that they give out - that leaves alot of effort in proper charging to be done by the users - which wont get done unless its a dumb way of doing it - they dont even charge correctly now with a dumb charger -

thats the last part that needs to be stupid proof - then its really plug and play - i dont see them giving out PL 8 and PSU and training everyone how to use them etc, - thats not going to happen -

[Burgerman]

Almost, it needs to take over the job of the PL8, and measure Ah used to give a measure of actual battery capacity remaining, and needs to watch the lowest cell voltage doesent drop below 2.5v...

That is what an ev cars embedded systems/controllers do.

[expresso]

Ok what i did now - - i changed the volt cut off to 22V from 18V - it also has an alarm setting - to alarm me with a beep if the Volts get low - just like the Monitor that shirley gave me - so i enabled that to yes - and it was set for 2 flashing bars when low battery -

just to be safe - i put that to 3 flashing bars - this way i know if i ever get that low - i will see 3 flashing bars which would be the RED - i have 3 Red bars - i would hear the Beep alarm - and if get that low at 22V - than it would stop i guess

now is that a good Voltage to set it at 22V - Does the battery pack drop under a heavy load - like up big hills - constant moving etc, - ? if thats the case i may have to lower the Volt cut off ? like lead - it drops low under load and then springs back up -

IF this drops low under load - it could hit 22V and then cut off the chair ? i make the changes to the program but didnt add it to the chair yet - is this safe to do at 22V - ? i wonder if i can just have the Flashing bars indicate to me when its low - but does that work together with the Volt cut off setting ?

[Burgerman]

now is that a good Voltage to set it at 22V - Does the battery pack drop under a heavy load - like up big hills - constant moving etc, - ? if thats the case i may have to lower the Volt cut off ? like lead - it drops low under load and then springs back up -

IF this drops low under load - it could hit 22V and then cut off the chair ? i make the changes to the program but didnt add it to the chair yet - is this safe to do at 22V - ? i wonder if i can just have the Flashing bars indicate to me when its low - but does that work together with the Volt cut off setting ?

Depends on how the programmer wrote the algo. And we cannot know that. So you will need to test. This is called development work. This is what you pay for when you buy a tesla!

Personally I would add a long cable to shirleys monitor. And stick it where you can see it. And compare that to what the r-net says untill you have it fine tuned. And figure out what it does. You need it to warn you, and then stop the chair before a cell group drop below 2.5V to 2.7V.

[expresso]

i am in no rush to do any more work on the battery now - but its something for the future to think about doing - i am not too over concerned just yet - the chances are - i never get that low anyway - i dont expect to do 40 miles rides at a time -

i will try to do 30 miles and 35 miles etc, - if i can even do that in a days time - thats a good idea in the future to run a longer wire and keep the monitor near me where i can see it -

so should i leave those settings the way i changed them then to 22V - ?

actually i am going to shoot an email to one of the engineers from PG - see what they say - maybe later tonight - my question to them would be -

1. if set to 22V - to cut off - at what volt would the flashing bars start to flash ? and when it beeps of low battery - when will that start to beep - at what Volts etc, - would it start at 24V to warn me - ?

thats what i will ask them - is there anything else i should ask or in a different manner ?

[Burgerman]

They wont know what you are talking about...

Yes leave it at 22v. I think it only looks at voltage if you are not driving.

[expresso]

its worth a shot - i sent him the email - lets see what i get back -

do you know - the flashing Bars and Beep alarm to warn of low battery - that would set off when it reaches close to the 22V i set ? so it should warn me before it reaches 22v - maybe 23 or 24V - i can beep and flash bars - gives me a little heads up you think ?

[Burgerman]

Its designed for lead. It will be taking account of peukert values, watching volts climb at rest etc. They will just tell you its not going to be accurate or work properly. And they dont have a clue about lithium...

[expresso]

yes - your right - he got back to me - and tried to explain about how the true charge works etc, - with some graphs he added -

i have the email but cant post the graphs - if you like to see it - i can forward it to your email - what is it again ? your email BM -

and the 22V cut off i put - the flashing low battery bars may start at 22.5v up to 24V - it can begin to flash for low battery - i figure it would start at least 23V - but either way - its not something to go by 100% -

i dont think i will reach that low anyway - i would have to get up very early and just ride for 8 hours non stop - i am not a morning person so that wont happen - i am going to try it one day to see if i can break my 23 mile record so far -

[Burgerman]

yes - your right - he got back to me - and tried to explain about how the true charge works etc, - with some graphs he added -

i have the email but cant post the graphs - if you like to see it - i can forward it to your email - what is it again ? your email BM -

Well that was predictable! No dont boher forwarding it, I know what it does. Its a waste of time and will never tell you the state of charge. They dont get it.

[expresso]

Ok looking very good - first time - joystick 29.7 miles - gps says 31.2 miles - not bad and the volts were still at 26V for the pack -

i am charging it up now - the video wasnt bad either - have to process it tomorrow and upload to Youtube -

heres the graph - monitor before i started the charge -

[expresso]

feeling good

Last night after some wine

those are my soldering iron glasses for the DB connector - i couldnt see with out them -

[expresso]

https://www.google.com/maps/d/edit?mid= ... YIvNVQ00Ds



i went over the GWB into NJ - visited a park there - didnt stay long - i wasnt there to explore today- then back and around the freedom tower - seaport and back home - was a excellent day for this ride - warm sunny - everyone was out -

[Burgerman]

No permission...

Ok looking very good - first time - joystick 29.7 miles - gps says 31.2 miles - not bad and the volts were still at 26V for the pack -

Chair distance isnt accurate, it just deepends on what figure someone entered in programming for its max speed, It "presumes" full stick is X mph (as decided by whoever configured it) multiplied by time. It thinks full stick always gives this nominal speed. So it is wrong on hills, and its wrong on lithium because your higher volts make you cover more distance because you go faster... Making it under read.

GPS is also distance x time. And can only even read accurately, or less than you actually do, if you have a detour it cant see due to loss of sattelite. So you covered 31.2 miles or more.

The worst accuraccy is when you measure distance on a short course like this: http://www.singletracks.com/blog/gps/gp ... cated-gps/

Its way better over a longer distance. Even so it is very accurate.

[expresso]

yes also alot of dead spots for GPS tunnels out of sight etc, i always have to do alot of hills - when riding around - still charging now - already put back 55ah and at 27V - and climbing - i say it may end up around 75ah put back - in that area -

[Burgerman]

31 miles x 2.28 Ah per mile (is what you used last time) means you will put back:

71Ah (you actually used) + about 5% because its not completely efficient on recharging.
So the PL8 will read about 75Ah returned. Leaving 34Ah remaining when you got home. Or 14.9 miles left.

My prediction...

[Burgerman]

You will start wearing out motors next!

Did it feel like a long way?
With addon you should go for the day somewhere.

My 6mph chair will go further per Ah with its radial tyres and lower speed. And its got 120Ah... So 20% more miles.

GPS tunnels out of sight etc

Deadspots have no affect on total distance unless you drive back and forth or around something while its dead, It just joins the dots! It thinks you went straight. This will cause it to read low or be correct.

But hills, extra volts, screw up the chairs distance covered completely... And cause under reading.

[expresso]

yeah i worry about the motors - but hey - insurance for that - - i already changed out the motors on my other chair - p222se - and i wasnt even doing this many miles then - insurance paid - they were billed something like $1700 each - now if they got paid that much - who knows -

my invoice when i got the chair back was around $4500 - two motors - etc, batteries - crazy - about two months - for quote and insurance to pay etc, parts ordered - done - they took my chair on a Mon. . got it back on Wed or thursday same week - i was able to use it during this time - chair was working but was pulling to the left some -

those were the big elector-craft motors that look so strong etc, - not so sure about it - but run fine for now - and are quiet compared to these smaller looking motors but these new smaller motors are faster and feel great - they have a constant wine to them which i never had on the others -

takes some getting used to hearing it all the time - i wont be surprised if they outlast those older electrocraft models -

[Burgerman]

Read above!

[expresso]

Read above!

i was posting when you posted that -

i went mostly straight for as much as i can - this way seems the best way to get to the bridge - about 10 to 11 miles to reach it - then cross it and back adds a few more -

i came back the same way - and continued - to go around the city - to add more miles to the trip - still not enough - i need to wake up earlier and do more if i want to reach 40 miles -

with the ADD ON - forget it - dont think i will need it - but who knows for kicks one day -