Mobility Scooter battery, which one...

[dishman]

I looked into this a bit more.

i was curious as on the website for this scooter, the company quotes up to 20mile range, but with no other information as to what D0D for the battery.

So after calling their tech department, I was informed that that figure pertains to doing a near 100% DoD on the battery.

From all my learning in the past few weeks I understand that it is never advisable to go below a 50% DoD for deep cycle AGM batteries, which would make the recommended range for this scooter actually around 10 miles.

So, based on my test, the original batteries I had in the scooter, which seem to have a possible 9miles at 50% DoD in them is actually still very good.

My only other suspicion is that the Tech departments are not actually that technically minded because the person i spoke to said that they recommended breaking in lead acid batteries by charging them for a long period when they are first received (which I understand is correct), but then doing a number of deep discharges (well below 50% DoD) and doing long overnight charges a few times (which, again from what I understand is not advisable).

But, my take away from this is that scooter ranges are often quoted at 100%DoD for the batteries.

 

[Harry Bloomfield]

My only other suspicion is that the Tech departments are not actually that technically minded because the person i spoke to said that they recommended breaking in lead acid batteries by charging them for a long period when they are first received (which I understand is correct), but then doing a number of deep discharges (well below 50% DoD) and doing long overnight charges a few times (which, again from what I understand is not advisable).

Any discharge below 100% on a lead-acid battery, will cause wear on the battery, and reduced capacity. I've never heard of 'breaking in' a battery. Leaving it on charge, is not good for a battery, but forgetting to disconnect the charger occasionally overnight, will do it no great harm.

All modern chargers, are carefully controlled, so they recharge fully, then switch to a trickle charge. Left permanently on a trickle charge, keeps the batteries warmer than they need to be, and can cause the electrolyte to evaporate.

Leaving the batteries in a partially charged state, can cause sulphate to form, so as soon as you get home, fully recharge it.

The battery gauges can suffer extreme volts drop through the wiring, when the scooter is being ridden, the only time the gauge is reasonably accurate, is when the scooter is first switched on, before it moves.

 

[dishman]

Any discharge below 100% on a lead-acid battery, will cause wear on the battery, and reduced capacity. I've never heard of 'breaking in' a battery. Leaving it on charge, is not good for a battery, but forgetting to disconnect the charger occasionally overnight, will do it no great harm.

Yeh, I have learned a lot looking into all this. Been very useful, thank you to all the responders.

Measuring the voltage correctly was key. Taking the measurement from the charging port was a big red herring, which initially made me think the batteries were toast.

Also, understanding that the quoted range manufacturers specify relates to running the batteries to being completely empty was also giving me an incorrect expectation as to the range.

It seems after all this that my existing batteries are actually in good condition still, with decent life left in them.

 

[Harry Bloomfield]

Any discharge below 100% on a lead-acid battery, will cause wear on the battery, and reduced capacity. I've never heard of 'breaking in' a battery. Leaving it on charge, is not good for a battery, but forgetting to disconnect the charger occasionally overnight, will do it no great harm.

All modern chargers, are carefully controlled, so they recharge fully, then switch to a trickle charge. Left permanently on a trickle charge, keeps the batteries warmer than they need to be, and can cause the electrolyte to evaporate.

I'll just add to that - It's important to understand, that batteries do self -discharge, and some scooters might have a permanent small load on the batteries, even when switched off [1]... If the scooter is unused for a while, it's very important to every so often, give them a top-up charge. Somewhere between once a week, or once a month.

[1] Mine, includes a permanently on, remote control alarm system, it doesn't cause much discharge, but given time, it will flatten the batteries.

Many second hand scooters, will have been parked, and left for maybe weeks, with no care being given to the batteries, so often the batteries will be wrecked.