S646se - Full LITHIUM Pack Project - First Attempt

[expresso]

yes i see what it can do - but not needed really - more work to hook up and take off etc, - i can check it when i recharge and get an idea more or less - keeping track of the miles used while riding - and give myself room for error -

should be fine i think - 30 miles - should be easy now - and i bet i still have more than enough left over - say 20% - but will charge tomorrow to get an idea - and then i know what 10 miles used up in Ah - add a bit more to be safe

[Burgerman]

Whay you need is an idea of Ah used om a long trip and back. It may be 2.5Ah per mile. Overall.

But the same chair used indoors or shopping may be 15Ah per mile if you mostly shuffle and turn. Same on an uphill...

[expresso]

i am just about almost done with the first charge - i will post when done

its showing about 28ah put back in - which means - about 30 miles total - i was expecting more for some reason

[expresso]

first charge results

[expresso]

PL 8 file - both the same - not sure if i did it right - try both if they work

[Burgerman]

27Ah returned is about 25Ah used.
Remember that you put about .5Ah or so back extra per 10Ah (as its not 100% efficient even with lithium). We saw that difference when discharging/recharging.

So 25Ah was actual used on 10 miles trip. You have 105Ah usable. So you would go 40 miles with 5Ah in reserve remaining? (Another couple if miles)

With the addon, thats another 36Ah added. So div by 10m/25Ah is another 14.4 miles extra. Grand total with both is 54.4 miles, and 5Ah left in reserve based on your own figures.

Not sure where you got 30 miles from? And remember that on a single longer trip, theres less starting stopping indoors, or moving about indoors proportionally per mile, so will do slightly better too.

I note that you are still charging at 30A?
And that my 120Ah pack on my green chair was predicted to do 45 to 55 miles, which looks to be correct or slightly under estimate. Since its a 6.2mph chair.

[expresso]

i just rounded the numbers off to be on the safe side - so 27ah returned - - i just said ok 30ah - x 3 = 90ah with 15ah leftover to be safe -

giving me 30 miles - so i can do about 40 and still be safe - not too low -

the only thing i can think of with the PL 8 setting is - its checked to run of PSU - thats set at 35A -

the battery supply side - is set at 30A - but its not checked off to use - so not sure why it would matter

but thats the only thing i can think of - will take a snap shot of next time to show you -

[Burgerman]

Set that to the max the power supply can do.
(Mines set 44A and my supply is 30V...)

Nothing is 100 percent efficient. And you are using the 24v supply to the charger which has to increase this voltage to 28.80v and still charge at 35A. Which isnt possible...

Your power supply is limited to:
24v x 35A = 840 WATTS MAX INPUT. (Its a 1344 watt OUTPUT charger!)

Your battery charge is set at:
28.80 x 35A = 1008 WATTS OUTPUT. (So it will need that WATTAGE plus about 10% in to be able to comply) Set to say 50A or more if your supply can do that. So you can charge at 40A if you want.

If fully discharged:
40A (or more if charger allows) if in a hurry.
20A (or less if you have a small charger) is a good figure if you have 5 hours to spare like overnight charging.

Your choice, lithium likes to be charged (or discharged) gently. Make a clone pre-set. Change only Amps. Call one RAPID charge, one OVERNIGHT charge.

[steves1977uk]

How many Amps is your PSU rated at? If its 47 Amp, then set the DC Current Limit to 45A. This will allow you to charge at 35A as thats the maximum current limit set in the preset.

Steve

[steves1977uk]

Set that to the max the power supply can do.
(Mines set 44A and my supply is 30V...)

Nothing is 100 percent efficient. And you are using the 24v supply to the charger which has to increase this voltage to 28.80v and still charge at 35A. Which isnt possible...

Your power supply is limited to:
24v x 35A = 840 WATTS MAX INPUT. (Its a 1344 watt OUTPUT charger!)

Your battery charge is set at:
28.80 x 35A = 1008 WATTS OUTPUT. (So it will need that WATTAGE plus about 10% in to be able to comply) Set to say 50A or more if your supply can do that.

I have mine set to 60A since I'm using a 24v 100A PSU. The most I've seen the PL8 draw is 49.5A when charging at 40A.

Steve

[expresso]

good idea - will make two presets - one for slow overnight and another faster - its ok if its a slower charge since i have another chair - and or would be sleeping -

my PSU is specs says 75A - 1800Watt - so that should be more than enough - unless its bullshit specs ?

[expresso]

http://www.ebay.com/itm/Power-Supply-24 ... 2518.l4276

[Burgerman]

Set max amps to anywhere from 60 to 70...

Be aware that your charger may be more powerful than your wall. Not sure how 110 works! But 1344 watts out may need 1500 watts input. And your power supply may pull 1800 from the wall.

[steves1977uk]

good idea - will make two presets - one for slow overnight and another faster - its ok if its a slower charge since i have another chair - and or would be sleeping -

my PSU is specs says 75A - 1800Watt - so that should be more than enough - unless its bullshit specs ?

Set the PL8 to 50A then, the PSU will easily cope.

Steve

[steves1977uk]

Set max amps to anywhere from 60 to 70...

60A is the highest allowed.

Steve

[expresso]

ok next charge i will do that just to see -

the charge cable does get bit warm - i can hold it with my hand - but i do feel its warm a bit -

thats at 30A - those 12awg wires are fine ? also being so close to the balance wires - - wont affect the small balance wires when it gets warm ?

if the pack likes to be charged slow - shouldnt even bother with a fast charge unless i really need the chair again soon after ?

[Burgerman]

Compare this perfect trace of 8S full big pack to when the other little addon pack was first rewired after the BMS was supposed to be balancing them!

PL8 CHARGER full big pack: download/file.php?id=4976&mode=view

Now this was the 36Ah Addon pack after several charges with a BMS in charge! It SHOULD have been in perfect balance.
First charge with PL8 CHARGER to find out and properly balance: download/file.php?id=4749&mode=view

It was, much as predicted/expected miles out of balance... This is why they are useless for charging and why cells die.

[expresso]

Compare this perfect trace of 8S full big pack to when the other little addon pack was first rewired after the BMS was supposed to be balancing them!

PL8 CHARGER full big pack: download/file.php?id=4976&mode=view

Now this was the 36Ah Addon pack after several charges with a BMS in charge! It SHOULD have been in perfect balance.
First charge with PL8 CHARGER to find out and properly balance: download/file.php?id=4749&mode=view

It was, much as predicted/expected miles out of balance... This is why they are useless for charging and why cells die.

yeah - no question which is the best way to do it - when you see it - then you know - when you dont see it - dont feel it - or just dont care - then its fine - BUT - for some - for what ever reason - it may be the only way - and if thats the case - and you take the good with the bad - you accept it as is with the BMS - if thats the only way -

if not - then PL 8 is the way to go - i am glad i got the Pl 8 and went that way - before i did damage to my cells etc, - but i had to invest in everything to do this correctly - not every can or not willing to get so much involved - what is simple to many is not to everyone - alot of things come into play -

first and foremost - Funds - - and fear of how to use it - lack of Knowlege - space -and time - effort etc, - i am the first to say - it was a bit of everything for me - knowledge was the biggest of all - space - well i gave up my living room for it some of it - now i have to clean up and fix everything nicely on the utility carts - CARTS - two of them i had to get - one larger - one small for the charger Psu etc, will keep it there and roll it where i need to plug in and charge as needed

so i dont see alot of people doing this - not that i know anyway - i could be wrong so well see - i will tell them who ever is interested - a 2 row 15ah cell - ADD ON - is a good start and they be more than happy i think with it
but they want to start off with a new set of MK 24 to connect too - and have to invest in the Pl 8 PSU and connect to computer - that isnt bad at all know that i think about it - everyone has a computer - or should have at this day and age
the biggest cost is the Cells -

i say $800 to $1000 to get that done on the safe side - i have the tools - so i can do it for them - i have most other little things - wires etc, - its doable - i can do it for anyone who may want it - but they have to learn how to take care of it and do the right thing or else waste of there money - not mines i wasted more than enough with this project

but well worth it now - winter is over - its all done - and i learned something - or else same old story this summer - looking at the greens - to go home - wasnt easy - charge cable a pain soldering - which i am not great at - but made it work

you know having the ADD ON Cable with the anderson on the charge also - i could have very easy just make a longer Balance wire and use two cables to charge - never needing to make the subd charger cable -

simple anderson to PL 8 - and balance wires to PL 8 also - two cables - easy to do - and not that much extra work to connect them - i am watching when they connect and disconnect that sub d - and i have to Consantly stress to them NOT TO Wiggle it off or bend it etc, - just PULL holding both ends -

its a habit when its hard to pull - you just try to wiggle it to loosen it up - i am afraid the pins will break - and i can see that happening - i may make a balance wire to keep ready in case that happens - and it has to be done in two parts -
and then connected again with the Male end going to the PL 8 - so will need two sets of cables cut in two - - one short cable with male to female - then the reg. cable to go to the PL 8 -

its do able - thats my back up plan if that ever happens - till i can make a new subd - and if i do - i didnt think of that before - focused on the ONE subd to charge - which is a great idea and its a nice solid connector -

but when you have too many hands touching it - - on second though - that sounds nice now -

[LROBBINS]

Normal U.S. 110-120V outlets are either 15A or 20A; both are in common use. If 15A you have ca. 1650 to 1800 Watts available, if 20A you have 2200 to 2400 W.

[expresso]

Normal U.S. 110-120V outlets are either 15A or 20A; both are in common use. If 15A you have ca. 1650 to 1800 Watts available, if 20A you have 2200 to 2400 W.

its 15A here - only the AC line is 20A -

all the rest are 15A -

[steves1977uk]

but when you have too many hands touching it - - on second though - that sounds nice now -

Touching what???

Steve

[Burgerman]

Expresso, your posts are a bit rambling and confusing to put it mildly!

[expresso]

yeah they can be - i have to work on that - recharging now - i adjusted the charge Rate -

[Burgerman]

To?

Did you change the power supply Amps?

[expresso]

yes to 50A - now it charges at 35A - just finished - looks good - wonder if i can lower the term. its at 250ma - now i think

sounds scary at 35A

[Burgerman]

So you used about 47 to 48Ah. Leaving 58 more you could have used.

How far did you go? Because you can double that and still have 10Ah left (4 miles?)

250ma is fine. Its very done! But 210 will be ok. Thats exactly 500thC termination. And change the 133 name to 500thC...

[shirley_hkg]

You guys killed one or two Hyperions every year.

I would love to see if the PL8 survived , and then getting one.

It's not cheap, compared to a dump charger which will last for 5--10 years commonly.

[expresso]

So you used about 47 to 48Ah. Leaving 58 more you could have used.

How far did you go? Because you can double that and still have 10Ah left (4 miles?)

250ma is fine. Its very done! But 210 will be ok. Thats exactly 500thC termination. And change the 133 name to 500thC...

Ok will do - i did almost 22miles - it was 21.56 mile on gps - i think the pack volt was 26.3V when started to charge

what does 133 or 500thC actually mean ? if you can explain in simple terms -

[steves1977uk]

You guys killed one or two Hyperions every year.

I would love to see if the PL8 survived , and then getting one.

It's not cheap, compared to a dump charger which will last for 5--10 years commonly.

Yes but a dumb charger and BMS doesn't end well, shorter cell life, cells way out of balance as seen by expresso's add-on pack when he charged it with the PL8 for first the time.

Steve

[Burgerman]

Ok will do - i did almost 22miles - it was 21.56 mile on gps - i think the pack volt was 26.3V when started to charge
what does 133 or 500thC actually mean ? if you can explain in simple terms

22 miles. 48Ah used. That means you used 2.18Ah per mile.
105Ah div by 2.18 = 48 miles... REAL WORLD DATA. (Thats about 65 miles testing using the manufacturers bullshit official ISO method!)

So on that basis you would have done 44 miles and still had about 4 in reserve.
But this will never be consistent and will vary every time as usage and weather, actual route vary. You may get more or less miles next time.

C just stands for capacity. So a 70Ah battery if charged at .5C would be charged at 35A.
And so a 70Ah battery with termination set to say 100thC would end at 0.7A.
A battery that is 5C discharge capable would be 5x its capacity in Amps. So a 70Ah battery can give 350Amps before damage.