Ah and battery meters and a trip to town...

[Burgerman]

Today I replaced a NVMe drive that had failed in my desktop PC. Its heavy and glass and took me about 45 mins shuffling around my room changing position over and over. That uses a lot of Ah - all that zero turning. And covers no miles. Battery gauge however is reading full. These are cheapie 80Ah AGMs from eBay.

Then I spent 40 mins watering all my outdoor and indoor plants in quite a large garden. Again a lot of shuffling about on grass and concrete. No miles actual covered lots of battery used. Again this stuff eats a lot of power. Batt gauge still shows full...

Then I went to get a ham and cheese panini in the shopping centre, 1.6 miles away. Took laptop, stayed around 1 hour. Read all the news, backed up this website/forum, and then went to the bank and back home. So another 2 miles.

So far no battery light was lost. All greens still lit. And now I am back on my bed after being up 5 hours. So far charging using the shirly zxd power supply set to 3 stage, 28.8V and .2 transition to 13.5V float. I have returned 22Ah and still charging merrily at 12A - its max setting for XLR. I expect that the battery will take around 30 to 35Ah to top it off in total. When you consider that you only get 35 to 40Ah from a fully charged grp24 battery at best before you run out of juice it makes you realise that this battery is really around 2/3rds+ discharged. While still claiming to be full... And that my total MILES is likely to be under 4.5

Whats the point of battery meters? Or estimated range? I know I can do 15 miles if I set off on the streets fully charged with this old lead chair. But only around 5 today. With a full battery meter still! Range estimates and battery gauges are all but pointless.

[expresso]

i have experienced this also but with lithium on my bounder last week - i normally ride alone and take long rides - i normally make it home after 40 miles give or take and my JS showing a number 5 - not bad for a heavy bounder with very tall gearing for speed

but this time - my friend came along - she has the 200ah pack i put in her chair - 646 8.5mph motors - she rides different than me- i like the fast lanes bike lanes etc, - she dosnt - i like the streets - she dosnt so it was a different style of riding for me - we stopped a few times to look at some other areas etc,

the total trip was 42 miles which i do easy on my own the way i ride - but this day - my JS numbers are running lower and started flashing at number 3 - thats never happened before - unless the time when i did 68 miles - so i knew i used alot more battery this time then ever before -

i figure my chair pack was about to cut off - and run off my ADD ON - but i wasnt sure how much was used there either - i had a flashing number 1 when i did the 68 miles -

when i got home - i recharged - my bounder pack used up 90ah - my ADD ON pack used up 50ah - thats alot of battery used for only 42 miles - my friends chair - she charged and used 85ah - about half of what can use safely -

what a difference - now i have to watch out with the bounder also with 180ah pack - not enough -

[Burgerman]

Its not how big it is its - no wait.

Is not how far you go its what you do with it... No wait.

Its not how far you go its how you do it.

This day ended up at 28.5Ah then goes to float. Thats around 2/3rds battery avalable usable power. And no loss of any lights. And also only around 5 miles. Thats 33% of what it CAN do if I just set off and go after getting up.

[hobie1dog]

i normally ride alone and take long rides - i normally make it home after 40 miles give or take and my JS showing a number 5 -
the total trip was 42 miles which i do easy on my own the way i ride - but this day - my JS numbers are running lower and started flashing at number 3 - thats never happened before - unless the time when i did 68 miles - so i knew i used alot more battery this time then ever before -
:

That makes my rear end hurt just thinking about sitting that long in my chair.

[expresso]

i know what you mean - i have some friends who lately have been having issues sitting a long time etc,

if you do have pain - its not good - between the J2 with overfilled Gel - Air tires etc, and this is with the bounder chair -

i dont feel that bad at all so far - when i use the 646 chairs - much much better in softness of the ride - Air tires feel great there

bounder is still harder ride but yet so far i been able to manage - could be just a good fit and cushion -

[hobie1dog]

The new narcotic pain patch they have me on now is finally allowing me to sit for 6-7 hours in my chair. I'm not a fan of it as it leaves me lifeless, it removes all enthusiasm for life. I just found a good source of edibles, so I'll then be able to quit taking 6 pills a day and get this patch off, and get to feeling some good sensations in my body again.

[terry2]

I love my smart shunt that tells me what I need.

As I do over 20 mile trips @11mph it's nice knowing what my cells are doing.

[Burgerman]

But thats the problem. You do not know. Thats the one thing you must know. You only know the total of 8S cells. As you get towards the end of your x Ah one cell will drop like a rock and the rest will be fine. And you cannot see that. And if theres any imbalance developing you cant know. And this is the thing that will kill off a cell. You only do it once and thats it. It would pay you to get a cell monitor if you are going long distances that use up lots of the pack. They are cheap.

[terry2]

But thats the problem. You do not know. Thats the one thing you must know. You only know the total of 8S cells. As you get towards the end of your x Ah one cell will drop like a rock and the rest will be fine. And you cannot see that. And if theres any imbalance developing you cant know. And this is the thing that will kill off a cell. You only do it once and thats it. It would pay you to get a cell monitor if you are going long distances that use up lots of the pack. They are cheap.

I do know.

When the cells was @3.0V I just went around the block till they started to fall fast.
Checked what my android app said and recharge .

I have done this 3 times now on long runs and shopping trips.
I have nothing better to do then test it out. And the Volts in the app match what the PL8 says.

Since my 8S is in 2 packs of 4.
I can monitor the whole 8S or each 4 pack of cells.
Anything funny going on between the 2 packs and an alarm will sound.

Victron are adding an option to watch each cell in a update soon.

[Burgerman]

No you dont.
As cells are used they change. Internal resistance changes. Capacity changes. And balance changes. So what works when you test it twice, doesent mean that this is much use 3 weeks later Or a year later. It also doesent allow for varying self discharge rates as they age. And the time you leave it between charging and actually discharging it deeply.

Thats why a cell monitor is essential if you plan on discharging them deeply by going a long way. Its also why those using a BMS might get a shock when it cuts power at half the noral range they expected as one cell drops low. At least with the PL8 and a PC you can see that they are at least balanced properly when charged.

Victron are adding an option to watch each cell in a update soon.

Then it will be safe to discharge heavily. Why do you think they are adding this?

[Burgerman]

I use one of these. I dont plug it in unless I already went about half range. https://www.youtube.com/watch?v=UIYCKYfNkiE

All you need to know. And cheap from bangood etc.

[terry2]

I use one of these. I dont plug it in unless I already went about half range. https://www.youtube.com/watch?v=UIYCKYfNkiE

All you need to know. And cheap from bangood etc.

I've had one them wired in since day one.

With the help of Irvine here. Pl8\Shunt\monitor all match each other.

Victron is adding loads because we ask for them on the forum.
They also helped me with settings.

As for BMS. There are very good ones coming out with GitHub support. And all programmable.
As long as these cells last another few years, I'm happy.

Can you turn in the notification for quotes on the forum please.

[expresso]

I use one of these. I dont plug it in unless I already went about half range. https://www.youtube.com/watch?v=UIYCKYfNkiE

All you need to know. And cheap from bangood etc.

i think i may get one of those - i would have to make a cable with a charge Sub end to plug it in my charge port on my chair - not wired to the pack itself

i am not worried much on the 200ah pack - as i am on the now 105ah pack i removed the ADD ON i had there - and i can easily use up that pack

i believe thats what happened 6 years ago when in first built it - that first summer - i was over excited and i must have over did it - - when i noticed one cell was bad - i must have went too low - i also crashed that first summer - and had no Fuse or Breaker installed for that first summer -

i survived it all - i replaced the one cell - added a breaker - and started using an ADD ON also with it - never had issues since with the ADD ON -

now i removed it - because the chair is too tippy with the seat moved back - i wonder if it was worth it - we shall see - but i am limited now with 105ah pack only - i say 30 miles to 35 at most with that chair to be on the safe side -

its my spare old chair - using it since both my new chairs are down waiting for repairs - adjustments etc, before i use them again - \

[ex-Gooserider]

The new narcotic pain patch they have me on now is finally allowing me to sit for 6-7 hours in my chair. I'm not a fan of it as it leaves me lifeless, it removes all enthusiasm for life. I just found a good source of edibles, so I'll then be able to quit taking 6 pills a day and get this patch off, and get to feeling some good sensations in my body again.

Be wary of that patch - especially if it's an opioid! They can be VERY addictive, no matter what the doctors say... When I first got hurt they got me hooked on the Fentanyl patch while I was in rehab... It made me stupid and sleepy all the time and had a really negative effect on my personality (all known and documented side effects) while not doing all that much for my pain....

Of course the doctors didn't want to do much to get me off it, so I ended up doing 'cold turkey' on my own, which was a week of pure hell - nausea, vomiting, spasms, etc... AND IT WAS WORTH IT!!!

I now have clear instructions in my medical chart (and I had to FIGHT to get them there) that I do not consent to any form of opioids for ANY reason (and STILL have had arguments w/ Doctors about it who insist the crap isn't addictive....) I just tell them that I went through hell to get that monkey off my back, no way am I letting it back in the room....

ex-Gooserider

[clairc]

I wish there was an easy way of knowing how much battery you have left. I've had my monster chair (a modded Quickie F55) for nearly a year now. I put MK 73ah batteries in it but recently it's been struggling on grass and going uphill, especially towards the end of a walk. Today after doing only 2 miles it started slowing right down on the grass and the battery light started flashing red. I got back onto the path and it was fine and the battery lights started to come back on. When I got home I stopped on the driveway, turned it off and on again and I was full green.

Is it time to get new batteries? I don't want to get stuck out on a walk as I go out on my own with my dog across the fields but I don't know if I should replace them now or hang on for a bit.

[Burgerman]

Yes. Now or before now! The inability to climb or roll on grass is because of battery resistance. The impedance. And the peukert effect. And thats exactly why a battery meter is useless. As you just displayed paerfectly.

But batteries only last so long. They begin deteriorating around 4 weeks from 1st use. They continue to do so until their abilities intersect with your usage. That can be 9 months or 10 years depending on many factors.


They die fast with a typical mobility charger as it both undercharges them and over volts them... So use a decent charger that charges them correctly. Then the next question is which charger. And there starts a massive discussion.

[ex-Gooserider]

And of course the best solution to battery issues is to do a Lithium conversion.... See plenty of other threads for details, but bottom line is longer battery life and MUCH better range...

ex-Gooserider

[expresso]

very long battery life - my first pack is goin on 6 years - feels the same as new - after a few runs this year - its charging up nicely

these are headways 15ah cells 105ah pack -

[expresso]

if i had lead - i would have used at the very least 6 sets of MK 24s - and still can only get a max range of 15 miles maybe -

i still get 35 miles - maybe 40 depends but 35 miles safely with this pack -

[Burgerman]

You can lead a horse etc.

We all know you get long life, tons more range, and it works out massively cheaper. But people cant be bothered to do the work or learn mostly. Once you have then you see how easy it is. But its not for everyone. I am visualising my mum with a soldering iron...