What is the recommended discharge rate lead AGM battery.

V

vicens

100 W
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I've been reading the forum. No meeting which is a high rate of safe discharge.

I have a scotter. Ride brand. Type ge1500. E1 model. Norauto selling. Is this.

http://ecomodder.com/forum/emgarage.php?do=details&vehicleid=9183

It has five lead AGM batteries 12V 18AH/20h.

has a controller 12 fets 30A and voltage cut 52V

I want to increase the power or change another controller 45A. To climb the slopes faster.

With settings 45A. It has a discharge rate 2,5C. Is it safe discharge rate for batteries?

The slopes where I would like to go faster are two. 100 meters each. go up to a speed of 20km / h

The scotter has a switch to limit the speed on level 45 and 38km / h. With the battery fully charged.
 
Some here might say the safe rate for lead would be about .1c. Peukerts effect is so severe with lead already, that 1c is pretty bad, let alone 2.5c rate.

Many types of lithium will also do better if kept below 2c, but with lithium you can fit, and carry the weight of twice as much AH as lead easy. As soon as you say the word hill, heavy lead really loses it's appeal too. I won't be the only one here to say, start saving up for some lithium. Meanwhile, leave your scoot as is, so your lead will last till you can get some lithium.
 
rated capacity on the last Lead acids i looked at (i think they were AGM) was given at c/100
i had to look twice to figure it out cause it seemed odd... but yep on a 44AH batt i could draw .44amps to get rated capacity.
they were oldish (two years) so i thrashed them like a dyin 'orse at 20amp discharge (.5C)and got 6AH out of them....
so what DD said...save your dosh for some LiFePO4 for a direct replacement.
k
 
2,5 C should be SAFE with good margins. Otherwise I'll be surprised.
I do 4 C under a few minutes on my electric skateboard with SLA's and they do not get hot. While doing 2 C on average i get around 4,5 Ah out of the 7 Ah battery.
 
For comparison's sake, Currie eZips use 10AH 24V batteries with a 35A controller. I think the eZips only pull the full 35A for a moment on take-offs, but hills can drain 10AH SLA batteries quickly depending on length, grade and load.
 
Lead ? It likes to be at full charge. So keep it fully charged at all times. If warm let kool down first. Charge at low rate for best charge. This way you will get the longest life. The hard part is keeping fully charged when in use. Bad to store at low state of charge.
Save your money for New age lithium battery it's better match for e-moto's
 
The batteries won't be damaged but you won't get very good range.
I ran some Enersys AGM batteries at nearly 10C for short bursts. 4C for long periods. They never got hot.
 
I start with many answers.

I know the Peukert effect. download faster there is less capacity available.

He planned to discharge the battery to 50% maximum. For 400 charge and discharge cycles before change.

A high rate discharge drain the battery quickly.

With a controller 45A with 2.5C discharge, only work in high discharge during uprooted and on the slopes. The slopes do not think are more than thirty seconds. In the worst case.

The maximum speed is 45km / h and a power of about 950-1000w, a 19A together with a 1C discharge is needed. With the button in the slow position of 38km / h 650W and 12A are needed with a discharge of 0.67C. so to speed Cruzero discharged at 1C. Excessive seems not.

I rarely use the speed of 45km / h. by 7km / h is 50% more consumption. Trying to go as fast as possible. Touch the battery during and after. and they were not hot. So I thought of climbing amps controller.

I also thought up speed. With 72V 1440W needed to go to 52km / h. They are 7km / h with 50% more consumption than 45km / h. But scotter is to go at a slow speed. It has small 10 "wheels. Brakes underpowered. Suspension short trips. It can be dangerous to go faster. And it is forbidden to reach more than 45km / h on the flat. I'll take 60V

I have a data sheet similar to mine in size battery. discharges appear 3C. is this.

http://file.siam2web.com/pcshi/files[document]/Longpdf/2013829_80530.pdf

It does not seem to malfunction with 45A 2.5C discharge at times. And for the comments. no problems.
 
A lithium battery has some advantages and other disadvantages.

Comparing the lead and lithium battery seems better for my scotter lead.

I can be wrong. Correct me.

Comparing different chemical:

The lead-acid battery 18AH / 20h can extract about 10A.
Lithium battery Li-ion or Li-con of 11ah can extract 10A.
Lithium battery LiFePO4 of 11ah can extract 10A.

I hope to do some 2000km a year. Some 10000km in five years.

In some 10000km I hope to some 400 cycles to lead-acid battery. With li-ion battery would be about 600 cycles. Because the actual capacity the smaller.

If the battery care. The lead-acid lasts 400 cycles. The Li-ion battery lasts 600 cycles. They would have to change after five years.

The lifepo4 should last 1800 cycles. 30000km and 15 years. Lifepo4 not think a battery that lasts 15 years. In this case. The extra cost of a battery of lifepo4 not offset by a Li-ion.

From a Li-ion and lead. The li-ion does not spoil if you leave at half load. and has a lower weight.

Noting that the li-ion weighs 7kg and 35kg lead. It seems much difference. But. The scotter lead with battery weighs 95kg. With li-ion battery would weigh 70kg. But. Adding the pilot are 215kg with lead batteries. and 190kg with li-ion batteries. The weight difference is small. The lead battery is cheaper. Here wins the battery lead-acid.

10AH battery with useful I can do 30km. If I need to have a range of 60km I have no space to put bigger lead batteries. If I can put one of li-ion 22ah. 90km and if I need I can put one of 33Ah. Here the winner is the li-ion.

If I have enough 10ah useful. But many more trips ago. about 10000km in two years. Every two years would have to change the batteries if they are lead or li-ion. Or every six years if they are lifepo4. Here the winner is the lifepo4. It is more expensive but pays for that change less often.

So a lithium battery is not always the best option. The best choice in price and needs.

When changing the batteries. I'll look again. This electric bicycle and scotter I like every day. It saves a lot of money. It might make more kilometers in a while. You might need a different battery.
 
not sure how you made up these numbers but a lifepo4 pack is cheaper for the amount of useful work you will get out of it over it's lifetime. SLA packs will never have their rated capacity but a lifepo4 pack will. it will produce the full 10Ah of charge if it has 10Ah of storage. lead will not. ever.
 
The folks who are excited about buying lead for EV's are the folks who haven't yet tried to get somewhere with lead filled EVs.

A lot of weight, a lot of bulk, and performance that delivers little more than disappointment efficiently.
 
He might see 400 cycles, but if he treated lifepo4 the same way by getting 20ah of lithium, 50% discharge, he could see potentially 2000 cycles. More likely, though, 250 lead, and 750 lithium.

If he keeps it charged, and really doesn't discharge more than half capacity his lead should last quite a while. Lead actually can soak up quite a punch for a short time, if the depth of discharge is small. Think of car batteries.

But if he's ok to haul that lead up the hill, then that hill isn't much. I tried that on a real hill, and the heavier I got with lead the less distance I made it up it. So if that hill is not so steep anyway, it will work for him. I just assumed that hauling ass up that hill, he'd dip way past 50% depth of discharge.

But one thing for sure, he talks like a guy who never tried lithium. :mrgreen:
 
For durancion cycles.
He was looking at the data sheet.

For long battery lead WP18-12SHR

f29d8l.jpg


It is 400 cycles. But charge and discharge is not met.

Samsung cell for IRC-18650-26F. It is 299 cycles. And the discharge capacity at 1C is 90% not 100%.

ae71co.jpg
 
To make a 60V 12Ah LiFePO4 battery with 45A maximum discharge. Recommend me what cells?

To make a 60V 24Ah LiFePO4 battery with 45A maximum discharge. Recommend me what cells?

It is to get an idea of price if I change lifepo4.
 
I think the only LiFePO4 batteries that can dish out that kind of discharge current are A123s.
You'd need about 5p of the M1 cells to get 11Ahr.
They also make a pouch cell I believe is 20Ahr.

"nominal" 60v would be about 20 series cells.
 
The scotter has voltmeter. To function well the voltmeter. better 18 cells in series lifepo4.

Lead-acid batteries are:

64V charged. 2.13V per cell.
52V discharged. 1.73V per cell.

To lifepo4 18 series batteries are:

64.8V charged. 3.6V per cell.
54V discharged. 3V per cell.

Do you find easy BMS LiFePO4 18 cells?
Is it easy to modify the voltmeter?

Voltmeter:

i4e49g.jpg


Is the voltmeter useful to know the remaining capacity with a LiFePO4 battery?

There is very little difference. between 3.3V charged. and 3V discharged.

2zfvc0i.jpg
 
Get a 20 ah lifepo4 was my advice. Then you have great range, and can do 45 amps with better ones such as headways.

But you could have a battery half the weight of lifepo4 and still have great punch with something like NMC.

Also, voltmeters will work better for guessing capacity left with that type lithium. On the other hand, with 20 ah there not suffering so much peukerts effect, you'd not be too worried about it anymore.
 
dogman dan said:
He might see 400 cycles, but if he treated lifepo4 the same way by getting 20ah of lithium, 50% discharge, he could see potentially 2000 cycles. More likely, though, 250 lead, and 750 lithium.

If he keeps it charged, and really doesn't discharge more than half capacity his lead should last quite a while. Lead actually can soak up quite a punch for a short time, if the depth of discharge is small. Think of car batteries.

But if he's ok to haul that lead up the hill, then that hill isn't much. I tried that on a real hill, and the heavier I got with lead the less distance I made it up it. So if that hill is not so steep anyway, it will work for him. I just assumed that hauling ass up that hill, he'd dip way past 50% depth of discharge.

But one thing for sure, he talks like a guy who never tried lithium. :mrgreen:
Click to expand...

Dogman, you keep repeating that a lead battery can't haul its own weight up a hill. This is false information. Most likely the motor was undersized and the extra weight caused it to overheat even more quickly. With a properly configured system, extra batteries wouldn't cause less range.
 
If it's better than 20ah. The making of 20Ah.

A friend commented to me. If I want more power. It is better to increase the voltage. Before increasing amps. With more voltage it is more efficient.

Can there be a problem with a 72V battery?
 
That's exactly what happened to me, the hill was both steep and long, the motor was only 1000w. 15 all uphill miles was too much for lead for me.

So, you want me to change my story? Change what actually happened to me? My personal experience with lead was short and sucky.
 
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