Battery ADD on pack - First Attempt -

[Burgerman]

Just charge it every 2 days if you dont go far.

[Burgerman]

viewtopic.php?f=6&t=4460&start=40#p84092

BMS...

[expresso]

thats scary - but the BMS is what suppose to prevent that from happening - i mean catching Fire ? isnt that one of its functions to begin with - - i mean that was its intention - to keep it safe etc, etc,

but turns out it does the oppoisite - no industry will sell a ready made system for a wheelchair with out ONE - if they even ever do - they cant assume the user is going to do what it takes to make it work without a BMS - i dont see it happening

i started to ride now - summer is here - going over the Brooklyn Bridge today - using the ADD ON chair - feels great - this is a huge leap forward for me - going to lithium - at the very least everyone should do a small ADD ON -

2 rolls of 15ah cells and your good to go - simple small - easy - and doubles almost your range - now the only thing that holds me back is the others i ride with - they still use Lead and always will - so i am limited - unless i am alone only or take a bus with them which i dont like -

i may do sometimes -

[steves1977uk]

2 rolls of 15ah cells and your good to go - simple small - easy - and doubles almost your range - now the only thing that holds me back is the others i ride with - they still use Lead and always will - so i am limited - unless i am alone only or take a bus with them which i dont like -

I'd tease them and say "Come on, keep up!"

Steve

[expresso]

there chairs are slower either way - with or without the lithium in them - hes just not into doing much in terms of taking control - he got new batteries - hes happy - he got the ones that i got stuck with - which made me take the leap into this lithium - they suck - cheap AGM - not even MK - no brand - anyway - the difference is this - he feels fine with them - dosnt feel or see anything wrong - so with something like that - you cant help - hes fine - hes happy - -

till one day he be stuck i notice now - how he would worry when going distance - yesterday - he didnt want to keep going at one point - because he is programmed in his head - just like i was with the Lead - that at a certain distance - you know you cant go any more - so he has to turn back - i was just getting started when he was done already -

big difference - anyway - i done it - and i will help anyone else here who wants to do it - but that has to be up to them - they have to do the research and understand a little about it and how to maintain them - charge etc, - i would do it for them if they wanted - i can help with wires etc ,etc, - i have so much now - tools etc, - but they have to be willing to do it - funds wise - at least the cells and charger etc, - the little things - i have so i can just do it for them - use my stuff -

but they wont even want to do that - i am willing to use my own stuff - but its still a investment they have to do - woujld be alot less than i spent - wish someone did it for me here also - but then again glad i did it - so now i know - dont know everything but it was a success i think - feels great - cant wait to use the full pack and start adjusting those settings -

i am still working on the ADD on for settings now - and having turn accle. 100 - works - now i am getting it better than before - going to 50 comp. today and adjust the turn rate a bit slower - foward a bit slower - keeping turn accl. at 100 and will do decell. at 100 also - and see how that works out -

[Burgerman]

there chairs are slower either way - with or without the lithium in them - hes just not into doing much in terms of taking control - he got new batteries - hes happy - he got the ones that i got stuck with - which made me take the leap into this lithium - they suck - cheap AGM - not even MK - no brand - anyway - the difference is this - he feels fine with them - dosnt feel or see anything wrong - so with something like that - you cant help - hes fine - hes happy - -

You can lead a horse to water. But you cant make it THINK!
Trust me I have the T shirt...

The biggest difference for you now, is FREEDOM to go where you want without worrying IF...
That difference is priceless.

Eventually you give up looking at battery gauges once you are used to it.

[expresso]

yes i gave up looking at the joystick on the ADD ON Chair - thats for sure - i can get a feeling depending how far i really go - i dont always just ride as far as i can - but the difference is now - that i get where i want to go - i can now ramble around there - and not worry - before i get there - where ever that may be - but have to get back - cant ride around much

today - wasnt a big ride - but i went over the Manhattan Bridge into brooklyn - rode around a few blocks there since i never been there - not sure where i am - so didnt ride too far -
then rode back over the Brooklyn bridge into the city - and rode back along the west side water -

was hot - i am trying to video it - but my camera is acting strange - i think its time for me to get a real go pro and mount it - so i can get a nice video - i have to see what it did today if anything at all


its a great view on the brooklyn bridge - i only done it a few times - but its like another world up there - vendors for ice cream - food - art - bikes people - hanging out - sitting - etc,

i didnt expect that myself - pretty cool actually - will try to get nice video - when i do - i post it - charging up now - feels great - i cant help anyone who just dosnt get it -
or cares too - so hes fine the way he is - this is why the industry wont change also - 90 percent are like that - so if they dont care - who cares

[Burgerman]

They are already programmed with what to expect. They are drones.

They dont even know they are programmed, and many like this will actually fight to keep things how they are... They dont like "change" its all excuses and made up issues and reasons why anything new/better is bad!

I still have a freind that drives a car with old carburettors and points ignition. He cant accept that modern stuff just works. Wont have one... He says you cant fix it when it breaks down. But claims he is ALWAYS fixing his and it will always keep going. Yet he doesent see the fallacy!

So we leave him covered in tools/old parts and a missfires most summer weekends!

[expresso]

yes - my friend - he has a chair thats almost 15 years if not more - old - its a very low end chair - no comfort - no back support etc

but hes afraid to get a new chair - he dosnt want change nothing but complains about how he gets tried when riding - too bumpy etc,

i tell him 1000 times - get a new chair - new soft cushion - wont feel as bad riding - i get tired also but i felt fine when he was all broken his back hurts - bumps this or that - he dosnt get it -

i told him many times - he can get my same chair - not the 646se but he can get the 636 which is the same just 6.5 instead of 8.5 - because hes afraid to speak for himself so just takes what they give him -

so i recommend to just get the 636- wont have to say anything - thats covered - would be faster than his chair now - better feel - comfortable - but he still waiting -

he has this chair - invacare - Nutron R51 XlR - - slow as shit compared to me - i have to keep stopping to have him catch up - he dosnt like to lead - which i always tell him to lead so i can stay behind him - but he cant lead the ride - so i lead and if i lead i cant get slow - but if anyone else leads - i stay behind them fine - he dosnt get that either -

its making it so much harder - he can get a new chair 636 quicker - with no effort if he just starts the process - but no hes afraid to deal with it - i gave up with him because his last chair which i tried to help him with -
he ended up with the R4000 pride - i told him NO - he did it - he hates it - slow as shit - slower than the his 15 year old chair - so he never used it - very little - in 4 years maybe a few dozen times - only if he has no choice - so i cant get involved with him anymore -

if he listened to me - he could have had the 636 with no effort on his part and a faster chair - but no
how can i explain to this person about lithum - haha - not me - he things feels hes fine - -then he is fine - before i met him - he never went past a 10 block radius

[Burgerman]

IF you take a PL8 with you, you can charge their lead chairs from yours if they run low... At 40A. At least you could if they had an anderson connector or similar.

[expresso]

they dont have the connector and i am not going to do that - the reason i did the lithum is so i dont have to carry a charger anymore if he wants to carry his charger and sit for 6 hours thats his problem -

i am giving advice that works - if he dosnt want it - thats his problem - i cant help someone who dosnt want to be helped - complain but does nothing - to change -

[expresso]

today i did a ride with my friend - he just got a new set of AGM batteries - Group 22 - using a Nutron RX51 Chair - 6mph - very basic chair

and we went around today - we ended up doing 15 miles on GPS - now his chair still had green - and my chair with the ADD ON was down a few greens when we got back - i though that was a bit strange - but then again i am not sure

my chair is a bit aggressive - alot of wheelies - jumps up - fast etc, etc, - compared to his - so i have to assume thats eating up alot of my battery - hes got maybe a 50A controller i am guessing - at the very best its 70A but i am not sure -

i know this is not apples to apples - but i didnt expect to loose those greens and his LEAD didnt - even though i know any min - he would go orange - red soon -

i just charged up - i put back about 50Ah - so how do i explain how great it is this ADD on - which it is - and i know it - but he feels its not needed - he did fine and better than i did - in his eyes -

[Burgerman]

2 things.

ONE.
You put back 50Ah. Thats MORE than you can actually get from a set of MK gel grp24 batteries.
He goes further on each Ah because his chair is weaker and slower. An 8mph chair uses 25% more Ah most of the time at comparable speed.

TWO.
When are you going to learn that the damned battery gauge tell you nothing! His lights dont mean a thing. Your lights only tell you that its either OK or its started eating some lead! You returned 50 total, so used about 45Ah. Only...

Stick tape over that gauge. You have about 45Ah usable from the lead alone. And 36 from the addon. So could have used 81Ah Or another 36 Ah to go... Better still fit an Ah meter as I suggested before.

Or look at it this way. You only took about 10Ah from your massive heavy lead batteries!

And an add on helps. But is nowhere near as efficient as a pure lithium system. Because as you acclerate and slow, and as you sit still the various battery types are charging each other back and forth and thats wasteful of energy. An add on helps but isnt perfect.

[expresso]

it does help and i like it alot - at least for this chair - its simple to make and add to it -

i am just comparing my last long ride at 22 miles - wasnt the same road etc, - i am just wondering when i have to start to worry - i had 30ah more to use more or less - which translate to what - about 8 more miles ? give or take

[Burgerman]

Or look at it this way. You only took about 10Ah from your massive heavy lead batteries!

Probably. 8 miles. Maybe more. But range doesent work that way.

If you do a bit of shopping with a girlfreind, you may kill a battery in 1 to 2 hours and cover about a mile... All that turning, sitting, going, stopping, turning back and forth eats batteries amazingly fast. Esp on tall geared chairs like yours. As it does before you go out! It does it faster with low tyre pressures or solid tyres. Faster again on a nose heavy chair. Small things make massive difference to range.

But why not use the full lithium chair, and add the Amp Hour meter I suggested at the time.

[expresso]

no use adding any meter that i cant get to or see etc, -

i figure i just use this ADD ON Chair since anyone i ride with is using LEAD anyway - i like this chair also - its nimble - snappy and wheelies alot - i havnt started on the full pack chair -

its been sitting for past 3 weeks maybe - i used it twice since i finished it up - weather just got nice so will start to use also - i will use it for upcoming wedding i need to go next week -

i wasnt going to charge it and just use it for that event - wont be alot of usage - then charge it - and start to use -

should be fine if i dont charge it before i use it for the event ?

[Burgerman]

http://www.wheelchairdriver.com/gopro/motoramps.mp4
Amp meter shown on ONE motor cable.

Turning rapidly on ramps or carpet in a fast chair can easily require 100A to 120A per motor.
Curbs, wheelies, hard acceleration fast chair = 80 to 120A per motor. A few turns then eats up a LOT of your battery!

Full speed in a fast chair in a straight line 11 to 14A per motor.
6mph constant speed in a faster 8mph chair as above 9 to 12A
Full speed in a 6mph chair as above 7 to 9A per motor.

Traveling along a transverse slope like the edge of a road, or a transverse angled footpath for drainage, can be 30 to 50 EXTRA all the way along. On a typical nose heavy rear drive chair as it tries to head downhill. A few sections of ths can HALF your expected range.

[Burgerman]

On the addon pack presets, change the balance start voltage to 3.40V. It will help.

[expresso]

yeah i guess - i ride it hard - usually each curb cut is a wheelie - and almost anything else that gives me a bit of push with full speed - i am having fun with it knowing i have the ADD ON to keep me going - alot of hills - wheelie up most of the hills easily - the lead is dragging along slowly up while i wheelie up - we had dirt - grass - - our streets are crap - sidewalks - only the very rich areas are nice smooth sidewalks - large also - wide - nice curb cuts - etc,

my chair is not nose heavy at all - its a lightweight compared to others - i have tilt on this chair only - this chair with no tilt would save some weight for sure - but not sure by much - 20 pounds at most -

either way its a light weight Quickie P222se - model

the full pack chair is a bit wider - looks to be heavier - but i saved a good 50 pounds now going to the lithium

[expresso]

On the addon pack presets, change the balance start voltage to 3.40V. It will help.

ok will try that - should i go even lower to 3.30V - would just take longer to finish which may be a good thing ?

i will do that tomorrow when i connect everything to charge again -

[Burgerman]

i go even lower to 3.30V

No, dont do that! Took me a year to get them to add 3.4 and 3.5 so we dont run into the problems that their default 3.3v balance caused!

[expresso]

ok will do 3.4V lowest - and see how it works -
would take a bit longer to charge - cant be too much longer - i dont mind - its fast now even at the slow 15A charge rate -

[Burgerman]

Will be about 4 mins faster... The reason it doesent take long is that you are fully charging 95% discharged lithium, but only replacing 12Ah of lead.

[expresso]

its a cloudy day today - but i have to test my new camera - so will take a short run - and change it to 3.4V before i charge - it wont be a deep discharge -

the full pack Chair - thats fine at 3.5V balance - ? this is just for the ADD ON Chair with Lead at 3.4V ?

[Burgerman]

We may change that too. At least for the slower charges. Dont worry about it its a tiny change, but I wanted to see the graphs first to see balance in use. Starting earlier makes it look better but disguises any problems.

[expresso]

ok - But wait - you want me to change it to 3.4V on only the slower preset charging ? 15A -

the faster charging preset at 25A - i can leave it at 3.5V ?


this is only for the ADD ON Lead Chair for right now -

[Burgerman]

Well try it. But def only 3.5v on the 30 or 40A charge.

[expresso]

what if we change the preset to go higher per cell - instead of 3.325V - i dont care if it goes over 28.2V for the Lead - lets say we do it for 28.4V total - give it a bit more - may help ?

i can get new Lead batteries if i wanted - i dont need to keep these for 10 years because of the ADD ON doing most of the work - i can get them every two summers easy - i can make a case for them each summer if i wanted to put the effort in for that -

but if i do it every two summers - i wont have to put too much effort in since the vendor will know its been two years since last time and wont give me a hard time with insurance etc, - just have to make sure its MK GEL - 24


i notice it cuts off CC before it hits 28.2V total - but as it works on the CV stage - it will reach 28.2V before charge is over -

If we raise it to lets say 3.350V per cell - shouldnt be too bad for the Lead ?

[Burgerman]

i notice it cuts off CC before it hits 28.2V total - but as it works on the CV stage - it will reach 28.2V before charge is over -

Dont set volts higher.

The reason the Amps fall BEFORE it hits 28.2v is because one cell or more has reached its preset limit. So since the charger can now only sink 1A balance, it must also throtthe power back to prevent that cell going above the voltage. This is the thing it should be doing.

Its what a BMS cannot do, and those can only balance at 1/10th of an amp! So the BMS cooks the cell instead repeatedly and then keeps disconnecting the charger over and over again. At about 3.8v...

[expresso]

ok i plugged it in now - changed it to balance start at 3.4v just on the slow charge preset - 15A charge rate - i left the Fast charge alone at 25A and 3.5V start balance

i did a quick little ride - a little over 10 miles -