Gel vs Lithium Batteries

[wes4dbt]

Yes. Depending on charge voltage and how charged they actually are before you start, how long at CV and how long at float. And depending on how long they were discharged for and how deeply and depending on how quickly you are with your measurements! And depending on how accurate the meter is. And how long they were in a discharged state before recharging. Remember that many cheap meters can be a few tenths of a volt out...

So the charger could have been charging the batteries @ 28.8 but then went to a lower voltage or float @ 26.4. Then possibly the surface charge would be lower than actual battery charge level (depending on multiple other factors). Ok, I see how the surface charge could be higher or lower than actual charge. Thanks

The main reason I was worried about the 26.4v surface charge was because the documentation said you need to bring your batteries to full charge 28.2v to keep sulfates from building up. But it seems I have no way of knowing the actual charge level.

Thanks for sharing your time and knowledge.

[Burgerman]

was because the documentation said you need to bring your batteries to full charge 28.2v to keep sulfates from building up. But it seems I have no way of knowing the actual charge level.

Sulfates dont build up due to voltages high or low. They build up due to INCOMPLETE charging. Or not recharging quickly enough. So sat on float charge for 4 or 5 days fully charges them. Also sat at a higher voltage for 8 to 12 hours (14.1V) or until current falls to a 500th to 1000th C whichever occurs first also fully charges them. Much faster! Thats what I do with the PL8.

In a fully charged battery all the sulfates are in the Acid in the electrolyte. Which is water and sulfuric acid. Which has silica gel xstalls added in a gel battery to make the electrolyte into a thick paste. There are no sulfates on the battery plate on a fully charged or fully saturated battery.

As you discharge it MOST of the acid in the electrolyte is "used up" leaving basically a water and whatever acid is left over solution as the electrolyte. Thats why the battery resistance increases as it discharges. Where does the acid go? It converts to lead dioxide and lead sulfate and coats the plates with each. When you recharge FULLY it converts back to sulfuric acid in the electrolyte. If you only recharge to 99% full then 1% of the sulfate remains on, and inside of, the battery plate as a white coating. If it remains too long it turns into a larger non conducting layer of xstals and they are then termed PERMANENT sulfation. And nothing whatever the snake oil saleseman tells you can convert them back again.

[wes4dbt]

I also think Pride is one of the WORST chair companies out there...

Yeah, a lot of people say that but not sure it's a fair statement. No doubt that companies like Permobile make a much higher quality chair. But I paid $3,800 for my chair, which has an elevating seat. A Permobile chair with an elevating seat would cost how much? 12 - 15,000. I think these two companies are meant for two different populations of power chair users. For about the last 10yrs I've been a part time power chair user. Basically when I went out shopping or some other business. Maybe 2hrs a day. I've always had Pride chairs and I've never had a breakdown. But I put very little stress on the chair and I'm paying out of pocket for the chair, so I'd say it's the right chair for me.

Now I'm 67 with a shoulder that's making it very clear to me that it's ready to retire, so I'm going to be spending more time in my power chair. It's only been three years since my insurance bought me a new manual chair so for now I have to make my current power chair handle the extra work or I'm thinking about buying a used power chair that has much larger batteries.

Maybe Pride makes the BEST of the WORST. lol

[Burgerman]

Other than build quality, and permobils crazy prices both pride and permobil are the two companies that I would avoid at all costs because they both mean that YOU as an end user are tied to them, and their experts to fix or program them. And they are not able or capable of doing this for you even if you wanted. I would never even consider buying any chair that I cannot program at the OEM level or better because it is an absolute essential. Its the primary thing that makes every chair usable on a daily basis.

So as well as GRP24 Batts area, rear drive in my case, centre footplate, and at least 100A control system (120A better) and 4 pole motors, and espesially an easily accessible OEM programmer. If a chair doesent have this short list available I wouldnt even look at it. These are the parameters that it must have to even get onto a literral shortlist. So permobil is ruled out at a stroke. Along with all modern pride stuff.

[wes4dbt]

I find it interesting how important being able to program the chair is to you. I've been very happy with the Pride controller (except the useless power display) but have no experience with the Permobile controller. I am looking at the M3 as a possible choice or the Quickie Q700 series. Are they comparable to the Pride? I bought a portable chair, KD Smart chair. The controller was so jerky, full on or full off, I hated it. Is this a problem with the standard Permobile or Quickie controller?

[Burgerman]

I find it interesting how important being able to program the chair is to you. I've been very happy with the Pride controller (except the useless power display) but have no experience with the Permobile controller. I am looking at the M3

The reason you have been happy is because like 99% of users you have no idea how accurate and linear and easy it is once the turn acceleration delays and turn deceleration delays have been removed. Because you never tried it. Trust me its night and day. So much so that I could never consider a chair where I could not do this. And more.

Other than the cheap chinese chairs that use dubious algos, and are mostly unprogramable by us, all mainstream powerchairs are EXACTLY the same. All of them have basically the same rediculous settings. It turns the joystick ito something that is a device that you slam around and then wait. Its not possible to be accurate when trying to get through a doorway for e.g. with any confidence. In comparison to a chair that steers when you tell it!

I have had people from all over the country come to me to get this done. NONE of them would let me put it back how it was. Not one!

Theres a post here somewhere yet again, that says the same thing. I will see if I remember where it is.

[Burgerman]

Found it. Yesterday.

Fantastically useful thread. I'd already started cupping the pod with my hand independently before finding the post, but the programming settings make a huge difference.

[wes4dbt]

The reason you have been happy is because like 99% of users you have no idea how accurate and linear and easy it is once the turn acceleration delays and turn deceleration delays have been removed. Because you never tried it. Trust me its night and day. So much so that I could never consider a chair where I could not do this. And more

Your probably right. This may be one of those "Ignorance is bliss" situations. lol

Glad to here that Pride/Quickie/Permobile controllers behave very similar to each other. Been worried if I buy a used chair from eBay that I could spend a lot of money and hate the controller.

[Burgerman]

Not just pride or permobil all of them! Every one.

[wes4dbt]

I was rereading some of these post and I came across the Victron Smart Charger reference.

Some how I missing this response from BM,

They have a custom user profile. You choose the right parameters to suit your battery.

Went to their website again but it wasn't clear to me what the charger is capable of doing. Are you saying that I can use an app to setup the proper (or close to it) charging voltages for gels? If so, this seems like a reasonably priced solution. Except it doesn't look like it has a XLR plug option.

[Burgerman]

App or better a PC.

Download victrons PC control software to see, click advanced to find a user setup. Not brilliant but adequate.

XLR? Why would it. Its not a wheelchair charger. Sooner or later you are going to need to solder something!

[wes4dbt]

XLR? Why would it. Its not a wheelchair charger. Sooner or later you are going to need to solder something!

Not true, I've made it 67yrs and I'm sure I can make it the few years I got left. Maybe I could do it, maybe not, us quads are not the most nibble. Seems like I could get a power cord made at an electronics repair shop. Not a lot of them around now a days but got to be at least one somewhere.

[Burgerman]

But you are making your life unreasonably difficult and expensive and the result less good. All for the sake of avoiding something that is really really simple. I can solder a couple of wires in less time and less effort than an endless hunt for solderless solutions and other people making you cables.

Obviously you've mistaken me for someone with wiring/soldering experience. Don't own a soldering iron, never soldered. But hell I'll try just about anything.

If you want an xlr plug on the end of a wire, thats literally a 60 second job. And likely done better, with less risk, time and effort than shipping the charger to someone else to do it. Were you not talking about going to a lithium setup? Or am I confusing you with someone else?

[wes4dbt]

If you want an xlr plug on the end of a wire, thats literally a 60 second job. And likely done better, with less risk, time and effort than shipping the charger to someone else to do it. Were you not talking about going to a lithium setup? Or am I confusing you with someone else?

I started the thread because I wanted to know if I could use some 50ah lithium batteries that were the same size as my 40ah batteries in my chair. I was encouraged to make my own but said it was out of my league.

It's a 60 second job if you got the right tools and knowledge and experience. I could make a custom software CRUD data entry system in 5 minutes. I've spent weeks helping beginners understand how to do it.

[Burgerman]

Well the degree of difficulty bears no resemblence. But your choice.

[wes4dbt]

Well the degree of difficulty bears no resemblence. But your choice.

Do you every sleep???? lol

[Burgerman]

Not really.

[Swan T.W.]

I was rereading some of these post and I came across the Victron Smart Charger reference.

Some how I missing this response from BM,

They have a custom user profile. You choose the right parameters to suit your battery.

Went to their website again but it wasn't clear to me what the charger is capable of doing. Are you saying that I can use an app to setup the proper (or close to it) charging voltages for gels? If so, this seems like a reasonably priced solution. Except it doesn't look like it has a XLR plug option.

The 8 amp charger [IP 65?] has an extension with ring terminals on one end, a plug on the other. Attach the ring terminals to the battery and plug the other end to charger.

[Swan T.W.]

Go to victronenergy.com Click on Blue Smart IP65 Charger and then click on downloads.You will see a data sheet with available extensions and plug ends.

[ex-Gooserider]

While we have quad members here that do their own soldering, it can be tricky w/o fairly decent manual dexterity... However it is not a terribly difficult skill - I have been part of public events where we taught basic soldering to kids as young as 5 - albeit able bodied ones... They didn't do a great job, but no worse than any other beginners I've taught.

That said, if you feel it is beyond you, try finding a local 'maker-space' or look for a ham radio operator, as maker spaces almost always do electronics (it is one of the easier shops to set up and equip) and Hams are also used to having to do soldering to build some of their gear - and both are very likely to be willing to help out...

ex-Gooserider

[wes4dbt]

Has anyone ever tested the Victron Blue Smart IP65 Charger to see if the app actual does anything? I mean if you go to advanced settings an set a custom charge voltage to 28.2, does the charger respond in kind? If so then would just adjusting the absorption and float voltages make a significant battery life difference compared to my standard cheap 28.8 (supposably) charger. Or would the charging curve/profile still be wrong and there wouldn't be much gain in battery life.

[Burgerman]

How long an answer do you want.

Its much better than any mobility charger I ever looked at.

Or I can write a hundred lines explaining why. That you likely wont understand. As long as you choose the CORRECT settings, and theres more than just voltages, it will be way better. Esp for gel.

[wes4dbt]

Or I can write a hundred lines explaining why. That you likely wont understand. As long as you choose the CORRECT settings, and theres more than just voltages, it will be way better. Esp for gel.

A short answer is fine. BUT, maybe a simple explanation of "choose the CORRECT settings, and theres more than just voltages". Because I have no idea what settings your talking about.

I'm also fine with a long explanation, I'm in no hurry and I enjoy reading your posts.

So whatever makes you happy. lol

[Burgerman]

In order to tell you what to set and why, I would need to reinstall the PC software which I just removed!

When you get it, go to advanced, go to user profile which lets you choose a few options for a user defined profile and ask me what to set each to, and why. So I can reply in detail!

[Burgerman]

Bugger. I will do it all over again. Install this:

https://updates.victronenergy.com/feeds ... taller.exe

Now without the actual charger plugged in then I am forced to choose a charger from the DEMO library. Theres no ip65. So I was forced to choose an ip12. So that means that all the voltages that I chose were for ONE battery. Its a 12V Charger... So when you get yours DOUBLE every voltage exactly. Also the one thing that it wont let me choose is the exact current. This ip12 allows 15A OR 30A. You need to choose 12A or less. The highest current that the XLR connector is supposed to take is 12A. Although I have tried 13A without issue. So set it to 10, 12 or whatever is the highest without exceeding this 12A limit. I think it does 12A which will be perfect. READ THIS ABOVE CAREFULLY!

Then set a USER DEFINED bunch of settings. And set it to EXPERT. Ignore the warnings for dummys.

Then set the following, bearing in mind the above!

NOTE you choose 12A max, here!
And DOUBLE each voltage.

And now the other half. My screen too small on this laptop to show all at once.
I forgot to change the temperature compensation on the screenshot. Stock is -16mV per degree C on a 12V battery. For MK gel it should be -6mV per cell. This means on that particular charger per battery bank. So you would need 12 cells @ 6mV so 72mV is the correct setting on a gel 24V battery. So change it to that.
http://www.wheelchairdriver.com/MK1.pdf

Then CHECK again, that you didnt miss any! All the figures should be as mine. With double voltage.

[Burgerman]

Just looked at specs again. It does 5A 8A and 13A. Use and set to 8A. Personally I would risk 13A and have on my R-Net chairs without any problems when in a hurry. But the chairs/manufacturer of the control systems say 12A limit. So that choice is yours!

Since you are not using large batteries 8 will be fine anyway.

[wes4dbt]

Yeah I had down loaded their software. btw - mine had the 24v IP65 as a choice, at the bottom of the list. But no problem your example is great, I can handle the math.

Thanks very much

You know I find it sort of shocking that MK puts out all this great information on batteries, especially Gel but they don't product a descent gel charger. It would just be a matter of a few parts with slightly different specs. Really wouldn't cost more the build. Then you could have a good charger for gel and another one for AGM's. Hell, then they could sell you two chargers instead of one for both. Maybe they don't want their batteries to last longer.

[Burgerman]

Bugger its 5mV per cell not 6... So the 72mV is wrong should be 60mV. I was trying to concentrate while my ex was yapping about something.

Yes its not so simple to make a good charger.

Take a look at these 2 graphs. One from my PL8 WHILE CHARGING a chair. Look how accurate and constant the voltage is. And one yellow graph using the PL8 to MONITOR a mobility charger. Not only is the voltage and current wildly fluctuating, and nowhere near correct, it stops charging way, way too soon. So it literally does everything wrong! Its hard to understand how you could even make a charger that is that bad if you tried! This is a stock invacare charger and was measured by a user on here.

[Burgerman]

And this is an INVACARE mobility charger. And its not faulty! They are all as bad. And not just invacare!

MONITORED by PL8. Not charged by PL8!
It SHOULD look like the idealised graph above. Or the PL8 Volt graph. Instead it looks like its trying to destroy the battery.

[wes4dbt]

No yellow graph but I know what your talking about, you posted it earlier in this thread.

Aren't you in the UK. Isn't it @ 4:30aam. And you say your ex is yapping about something. I don't even like the sound of my own voice at 4:30am. lol

You keep slipping in these extra post while I'm replying