Group 24 cells

[foghornleghorn]

Any situation where I need something to be idiot-proof I use coloured electrical tape to mark the thing they are allowed to do.

Ventilator ON button marked
Charger ENTER button marked
Matching red line on hoist and bed for positioning
Matching red line on hoist and toilet for positioning
etc

Anything where it is possible to set a default for initial turned on state like a wheelchair is programmed to be at its slowest speed when first powered up. It also gets programmed to shut down after 60 seconds of inactivity because people never remember to turn things off then wonder why if they lean on the joystick 10 minutes later they get both their legs broken

[jefferso]

Then press ENTER , till she see CHARGING .

Itsn't it simple and straight ?

Certainly you'd think so, but unfortunately not! I hide any presets that might confuse the dear ones and tell them to press Start until they see CHARGING and apply for guidance if they do not. *

I think mine wants about 10 button presses, depending on this and that.

* A scenario a dear one or an aide may achieve by pressing Back enough times and then Inc or Dec.

Absolutely possible for a mistake or miscommunication for things that seem very simple and straightforward for us. One advantage of something like the Permobil charger or the Victron is that it starts charging as soon as it's plugged in to the chair (assuming it's plugged in and turned on at the wall). Not that it's not possible for someone to make a mistake with those steps either, especially at 2 or 3 in the morning. I listen for the right sounds but often have to ask for confirmation. The Victron is nice because I can check on my phone with bluetooth.

One thing I noticed is that some people have a tendency to only read the first line of something. I ask what does it say? "Set charge rate?", I ask anything else? "No". Nothing under that? "oh, 30.0 A".

[jefferso]

Any situation where I need something to be idiot-proof I use coloured electrical tape to mark the thing they are allowed to do.

This can be very useful for so many things. I have white tape by the Enter button on the PL8. Also white tape on the Anderson SB50 receptacle on the Permobil C500 (hard to see for some people on the black chair without a bright light).

In the U.S. all busses had straps they'd attach to the wheelchair. It was so difficult to explain the attach points on my Permobil C500. The drivers had to deal with manual chairs, scooters and power chairs of all different types. Some would see it right away, others would try to wind around the footplate. My brother marked the area with orange tape and put green tape on the attach point. I'd say something like "inside the front wheel, below the reflector, the green bar in front of the orange" and hope for the best.

[Burgerman]

Remember that the average IQ is just 100. I struggle to communicate with the average. These are the ones that have no idea which political parties stand for what but have strong opinions about who to vote for. Listen to the first 4 words of an order at the mcdonalds and so get it wrong every time. Try to help by holding a door open, by standing bang in the middle where I need to go to get through. Etc.

And thats mr average. But mr average isnt on the bus. Remember that by definition half the population are below 100... And those that are above average tend not to use busses or work on them. They are the ones with cars, good high paying jobs etc. On average. The engineers, doctors, self employed, bosses, politicians, pilots, professors etc GENERALLY are not found working or using a bus.

So best of luck. Unfortunately while carers may have many positive and caring attributes it tends not to be a high IQ type job. Most of mine dont do fractions, cant work computers, dont read or understand or grasp simple stuff quite frequently. Or THINK they have, say they have, till you see what they are actually doing...

Theres no fix for this. Its just human nature. You are stuck with it. Drives me nuts.

Any situation where I need something to be idiot-proof I use coloured electrical tape to mark the thing they are allowed to do.

As a frustrated freind who sold nitrous systems for boy racers once said, "I keep on updating the instruction because I try to make it idiot proof". "But they keep on bringing out better idiots".

[biscuit]

My charger, bed, lighting remote etc. buttons are coloured self adhesive acrylic rhinestones.
https://amzn.eu/d/0hP2DMnA
Handy tactile markers, especially the 5 petal ones.

[jefferso]

My 160Ah pack weighs 24.3kg.

A single Permobil AGM Gel weighs 23.9kg.

A single MK Gel weighs 22.6kg

[Burgerman]

Amazing that you can get 3x the range, 10x the lifespan, from something that is now half the price, half the weight and 2/3rds the height.

And if you dont mind them being a bit explodey you can do even more range with lithium ion cobalt (phone/laptop/tesla) type cells. But I do.

The 230Ah cells from EVE are 4.11kg each. 32.88 kg for 8.

[jefferso]

I was a bit worried that the length of the pack is a bit more than the two MK Gels next to each other. But when putting it next to two Permobil batteries, it seems just about the same so I hope it will fit lengthwise. Width and height won't be a problem.

[jefferso]

I have 2 MK gel batteries manufactured in 2019 which were stored for more than a year so probably have no real capacity left. And I have 2 Permobil AGM/Gel batteries from 2022 which might have 50% of their capacity left. Does anyone have any recommendation on how best to get rid of them? I thought maybe I'd list them for £10 on Gumtree and see if anyone is interested.

I'll keep my current MK Gels as backup once I finally get this pack installed.

[Burgerman]

In the UK, scrap metal merchants will give you a few quid for them. As they want the lead.

[jefferso]

When assembling the pack, despite admonitions to be careful, a spanner made contact across a couple of cells and made a scary spark. It destroyed part of the stud and nut on the negative terminal of cell 4, but the pack so far seems normal and balanced fine. I was worried it welded the nut but it loosened and re-tightened without much trouble. For subsequent work, the other end of the spanner was covered with the finger of a nitrile glove and electrical tape.

I got some Battery Terminal-Cover Boots Insulating Protective Lug Cap 12x20mm from ebay.

https://www.ebay.co.uk/itm/375521793950

They don't fit exactly but seem to be doing a decent job of covering the studs and interconnect and balance wire ends.

[Burgerman]

Smaller versions of those terminal boot covers are also available on amazon. I have some here.

[jefferso]

Smaller versions of those terminal boot covers are also available on amazon. I have some here.

What size do you think would work best?
I also see 12x16mm

https://www.ebay.co.uk/itm/383045679251

Not sure that I'll ever take them off now that they're on, but might be good to have some better fitting spares.

[ex-Gooserider]

I have 2 MK gel batteries manufactured in 2019 which were stored for more than a year so probably have no real capacity left. And I have 2 Permobil AGM/Gel batteries from 2022 which might have 50% of their capacity left. Does anyone have any recommendation on how best to get rid of them? I thought maybe I'd list them for £10 on Gumtree and see if anyone is interested.

I'll keep my current MK Gels as backup once I finally get this pack installed.

In the US, many auto parts stores and some auto repair shops will give you either cash or store credit for dead 'automotive' batteries - I've never had a problem with them taking chair batteries as they are lead and the same size / weight, so effectively the same thing as far as the recyclers are concerned.

ex-Gooserider

[Burgerman]

Not sure yet. But I was looking at smaller ones than your image shows. And some rubber ones. Will find out when the eve cells arrive.

[fishinjunky]

your pack looks good and organized . I also used those boots on my pack. We did the same thing with a wrench but it was on the lead battery luckily . We tapped the handles on all our metal handled tools for building a pack.

[Burgerman]

Lots of amps flow from batteries! Thousands in fact.

[jefferso]

Does a DC circuit breaker care which way the electricity is running through it? My original plan to connect the long grey cable from the breaker to the red positive cable, then the short grey cable to the positive of the battery pack won't work because the short grey cable won't reach the positive terminal on the pack. So if I connect the short grey and the red, then use the long grey to attach to the positive terminal, it should reach, but I think it will reverse the direction of the electricity.

[Burgerman]

No. Its just a bi metalic strip. It bends and opens when the current warms it up.

However, most of these things are crap. And they start tripping out at lower loads as the contacts get a bit oxydised and so heat up too fast under even light loads. And they dont trip under very high loads sometimes for too long!

I prefer to just use a 150A MIDI fuse. Look on amazon. These are tiny, have a 5.5mm hole at each end DRILL that slightly to 6mm. Then it can bolt directy to a battery terminal. And then it can go between any 2 cells.
I am considering adding a 200A one between EVERY one of my 8 cells for safety reasons. Not needed but ...

[Burgerman]

Have you tested this yet?
You are going to be surprised how far you go, and how little you put back!
Even 160Ah is a lot. And your chair will be more responsive too. Less weight, and almost no voltage sag like lead, and it starts of about a volt or so higher and stays there all day.

[Burgerman]

Get yourself one of these:

https://www.amazon.co.uk/ISDT-BattGo-Ba ... B07WZFS7D8

It has a nice colourful bar graph display, and shows you your battery state. Its accurate AT THE ENDS, and its less accurate everywhere else because of the nature of the super flat discharge curve. But its not bad.

You need an 8S balance lead. Or two. If you cant find a 600mm one, get 2 300mm ones. On the ISDT BG-8S end, plug it in... On the other end add the 9 balance wires to another one of your charge cable connectors. It rolls up small. Esily goes in a pocket or a small string draw bag you ca hang on the chair. Mines old and a bit scratched. Its a bit toy like and plasticy... But its pretty good for our purposes. I used it initially so I could get some idea of what was happening. But now I ave a good feel for whats going on just by looking at the R-NET meter, judging distance/work, and see what I put back with the PL8. For a week or two I noted the precentages, and the distance (on the joystick - reset the trip miles!) etc until I could get a grop on how it all worked. I no longer use it. I wil do on my bigger 230Ah pack whan it arrives for a while. See how many days I can go...

Just plug it in every now and again to get a quick idea of battery state. Dont leave it connected if you are not using he chair as it slowly drains cells 1 and 2 to power itself.

Its also user calibratable. Quite easy to do. If you have a decent multimeter that you trust.
Also does a bunch of things that you wont need or want with RC gear. Ignore that.

[jefferso]

No. Its just a bi metalic strip. It bends and opens when the current warms it up.

However, most of these things are crap. And they start tripping out at lower loads as the contacts get a bit oxydised and so heat up too fast under even light loads. And they dont trip under very high loads sometimes for too long!

I think this is the one. So far it hasn't tripped with the lead acid batteries. It's in the circuit now. I'll see how it works with the new pack.

https://chintglobal.com/products/nxb-12 ... aker-8-700

[Burgerman]

While it works, why not. Much of this depends on the user though. Serious programming, drive it like you stole it and it will trip. If you dont it wont! Unless its faulty or a bit oxydised.

One thing. Some are relatively high resistance. (its why they get hot and then trip to begin with) If its between cell 4 and 5 and you see funny balance curve issues here that will be the cause. If that happens then connect to one end of the battery instead.

[jefferso]

Have you tested this yet?

I haven't tested it yet except for turning it on and moving it around in the room to a different position. I just did its first charge inside the chair. I'm doing a bit of discharge now since I'm not sure if I'll get to use it tomorrow.

I still have a few things to do. There's a finger's width of space on each side so it needs something to keep it from sliding side to side, though it's wedged in front to back pretty tight.

I have to figure out how to route the charging cable out. Right now it's coming out the side. I temporarily taped it up so I can use it in the house. I might have to cut a hole in the top plastic shroud big enough to pass through the connector.

[jefferso]

The circuit breaker is between the chair positive cable and the pack's positive (cell 8 +). At least I hope so, if I've done what I think I've done. So it's not involved in the charging at all. I should probably add one of those fuses to the charging circuit.

Here's how the charging cable comes out right now from the side towards the back.

[Burgerman]

Have a think before cutting great big holes!

[shirley_hkg]

The stock breaker is fine.

You need something robust , non conducting here. 1/4" plywood , one at each side, and one underneath.

I ordered a U-shape plastics.

[Burgerman]

ebay 3mm acrylic sheet in black, or blue, cut to order, same size as battery?

https://www.ebay.co.uk/itm/355777364076

[jefferso]

When I was discharging, the wheelchair controller screen seemed to show no green bars. I couldn't understand why it would suddenly go down but figured it might return to normal when I finished the discharge. It was the same after unplugging the charger. I asked my friend to confirm and he said all three green were lit up even though when I looked at it, they seemed dim. Turns out if you look at the joystick controller screen from too far to the right side (I never normally see it from the right side), the green shows up as dim. It was actually showing full the whole time.

[jefferso]

I had some scrap wood flooring which fits really snugly in both sides so it's now wedged in there.
I have a few layers of acetate and tape underneath but no wood or acrylic under it yet.
Still not sure how to route the charging cable. I was thinking of cutting along the inside edge of the plastic shroud so it could just be a small notch but the seat rising mechanism travels along that edge so it might interfere so might have to revert to the great big hole idea. It's now taped to the rear castor support temporarily again. I might have to revert to the old batteries for a while if I can't get it resolved tomorrow.