Prius batteries for a mobility scooter ?

[CompoSimmonite]

The pair of 12v SLA batteries have died, yet again, on my mobility scooter so I'm thinking of using secondhand battery packs out of Toyota Prius. They are 7.2v Ni-MH.
What is the opinion of doing this - worth a try or silly idea ?
Cheers

 

[zx9]

The pair of 12v SLA batteries have died, yet again, on my mobility scooter so I'm thinking of using secondhand battery packs out of Toyota Prius. They are 7.2v Ni-MH.
What is the opinion of doing this - worth a try or silly idea ?
Cheers

Don't know, but it sounds like a job for Colin Furze.

 

[Wallace]

What make are you using? After a short spell working for a company on disability equipment I was disgusted at the cost of batteries, their lifespan and particularly the warranty.

 

[CompoSimmonite]

What make are you using? After a short spell working for a company on disability equipment I was disgusted at the cost of batteries, their lifespan and particularly the warranty.

I'm on the third set. Can't remember the previous two makes but current are Lucas. They run out at around £150 a set and that is with them being VAT free !

 

[The_Yellow_Ardvark]

What Ah are they?

I ask as 12v 24Ah and up are used in Fire Alarms.
The connections are similar to ones I have swopped out in other scooters.

 

[eddie49]

Changing the battery type from SLA to NiMH should not be much trouble in the scooter, just voltage and capacity to consider, but any "fuel gauge" type displays may no longer be accurate. The real problem will be the charger; the required charging methods and cut-off/trickle options are quite different. It will work, but may not be safe and will affect battery life.

 

[a111r]

Lithium ion cells are starting to appear on new models in this mobility sector.
There has already been a domiciliary fatal fire incident.

 

[Wallace]

I found Yuasa gel batteries to have lasted well in most scooters used daily but the non Yuasa replacements were awful and overpriced cheap rubbish. Most of the scooters with their batteries may have been sitting in warehouses a year or more on top of transport from China and failed before warranty or more often than not just after and their replacements were not up to snuff.

One customer I went to asked if she could buy better batteries than the ones we supplied as they did not last like the original set that were still in the garage. Her boyfriend showed me them, Yuasa and they still held a charge. Spotting a clean and tidy bike in the garage we started shooting the chit and I asked if he had looked at the battery specs on her wheelchair and they might consider the higher capacity battery option. I gave them a quote for both sizes with the battery numbers and left them to it. Next service I get the story, high capacity Yuasa fitted £400 cheaper than our own brand low capacity

The Lithium batteries were eye watering on cost new and there will be many a scooter rotting away as buying another scooter can be cheaper than a new battery.

Some of the motor controllers are very sophisticated and may not work correctly with a different voltage. Most require specific software, codes and leads to access them and to start with I found it amusing diagnosing a faulty mobility scooter with a laptop!

 

[Bravheart]

Those batteries should always be plugged into the original charger and left plugged in when not being used, they will be discharged/charged and conditioned and may help lengthen the lifespan.

 

[The_Yellow_Ardvark]

If you know the aH of the batteries. Pop along to a company who deal with fire alarm supplies.
ADI Gardeners as an example.
You will get them cheaper than from the mobility scooter supplier.

 

[bigegg]

There's a group on FB - something like "18650 powerwalls" - which is dedicated to repurposing li-ion "batteries" from (amongst other things) laptops and electric cars.
Might be worth a browse? Laptop batteries are IIRC, c.3Ah and 3V per cell, and work out about 50p per cell.
It's just a matter of soldering/welding the cells together in the correct configuration to get the correct output and capacity.
(After dismantling the batteries, and testing the cells)
There's usually 6 or 8 cells per battery, and it's usually just one that's gone bad)

 

[eddie49]

Going SLA -> Li-ion, as opposed to SLA -> NiMH would open up a whole new can of worms. You would need to parallel as many 18650 cells as needed to get the required Ah capacity ( = range ) , and also the current-delivery factor of the chosen cells, known as the "C" rating ( = maximum current draw of the scooter motor(s) ). Then put 3 of those parallel strings in series to get roughly 12volts, add a Battery Management System ( BMS ) board, and you've got one of the SLA batteries. Alternatively, 6 cell-strings in series would give you the needed 24 volts ( you said it had 2 x SLA ), with a 24v BMS board.
You need the BMS in particular to avoid over-discharge of the cells, which can be dangerous.
Then you would need a Li-ion capable charger, with either a 12v or a 24v output.

If you decide to investigate going the Li-ion route, look up "e-bike" batteries. They are often 24v, but I'm not sure the typical Ah capacity would give you the range you need. E.G. : https://www.ebay.co.uk/itm/174459064160

 

[CompoSimmonite]

What Ah are they?

I ask as 12v 24Ah and up are used in Fire Alarms.
The connections are similar to ones I have swopped out in other scooters.

The current, dead, batteries are 55Ah but possible to fit far larger

 

[The_Yellow_Ardvark]

The current, dead, batteries are 55Ah but possible to fit far larger

60ah are cheaper from a Fire alarm supplier than you would think.

 

[CompoSimmonite]

Lithium ion cells are starting to appear on new models in this mobility sector.
There has already been a domiciliary fatal fire incident.

Not interested on Lithium as a pair would cost more than I'm willing to pay. I can stand and walk very short distances (say around Lidl / Aldi but places like Tesco Extra are at my max and very tiring / painful after) but use the scooter for local running around and outdoor events like car shows where I'd be out for hours. Not much fun getting old but to be fair I've had mobility problems all my life due to slightly twisted left leg and three compound fracture to right. Add excess weight, arthritis in right knee and left knee that easily dislocates have been final straw - hence accepting a scooter need to be used occasionally even in large supermarkets.

 

[ukracer]

I

If you know the aH of the batteries. Pop along to a company who deal with fire alarm supplies.
ADI Gardeners as an example.
You will get them cheaper than from the mobility scooter supplier.

If it's costing 75 quid a battery they won't be fire alarm sized.

 

[ukracer]

60ah are cheaper from a Fire alarm supplier than you would think.

Do they use that large a battery a lot then?

 

[The_Yellow_Ardvark]

Do they use that large a battery a lot then?

Can do. One system I maintain(Help, it is a 4 engineer site) has 12 panels in total as a Network.
4 have 2 x 60ah 12volt dc battery. The rest have 2 x 24ah 12volt in them

 

[The_Yellow_Ardvark]

I

If it's costing 75 quid a battery they won't be fire alarm sized.

Yes they can.
They size of the battery is dependant on the standby requirement.
Most domestic only need maximum of 2 x 12ah 12volt.

 

[ukracer]

Can do. One system I maintain(Help, it is a 4 engineer site) has 12 panels in total as a Network.
4 have 2 x 60ah 12volt dc battery. The rest have 2 x 24ah 12volt in them

Amazing I though they would all be small capacity. Anyway have you any links to suppliers. I found a few but just one battery is around the 200 mark. I can't find any sensible prices.