Erato 1500W batteries going down

37 posts / 0 new
Last post
doorframe
Offline
Last seen: 14 years 2 months ago
Joined: Saturday, July 19, 2008 - 13:06
Points: 25
Erato 1500W batteries going down

I have an Erato 1500W with 12V 38Ah x 4. Range is down to about 10 miles, and just managed to crawl onto my drive way yesterday. Been getting steadily worse (as indicated by battery meter on dash, and lack of 'zip' after a few miles) for a couple of weeks, but now suddenly nose-dived into the red well before the end of my usual journey. I'll investigate after work tomorrow, and hope to find just one of the batts has failed. I'm struggling to find a supplier at a reasonable price in the UK, and I can't justify £80 - £100 per battery for replacement SLA's. It's only 14 months old, and was supposed to save me money, not cost me an extra £400 every year. Can anybody point me to a UK seller with good quality batts at reasonable prices? Mine are supposed to be Greensaver...I'll find out tomorrow.

In another thread, JeanLuc34 says

Hi, i'm also interested to change my 48v sla batteries on my 1500W scooter.

Same here. But there was no feedback to this. Can somebody enlighten me as to the feasibility and approx cost of this?

Thanks for reading this. Doorframe.

doorframe
Offline
Last seen: 14 years 2 months ago
Joined: Saturday, July 19, 2008 - 13:06
Points: 25
Re: Erato 1500W batteries going down

In another thread, JeanLuc34 says

Hi, i'm also interested to change my 48v sla batteries on my 1500W scooter.
Same here. But there was no feedback to this. Can somebody enlighten me as to the feasibility and approx cost of this?

Thanks for reading this. Doorframe

.

Sorry ...missed the bit that said change to LIFP04... whoops

Thanks again...Doorframe

doorframe
Offline
Last seen: 14 years 2 months ago
Joined: Saturday, July 19, 2008 - 13:06
Points: 25
Re: Erato 1500W batteries going down

OK...no response...

More info... Batts have turned out to be ELECTIER, which Mr Chen in another post admits are crap. Cheers Chenny. I've always charged them within an hour of riding, and then within 7 days of non-use, using the 48v charger that came with it. Running the bike on the stand at full throttle for over an hour with Full Beam on for extra load, with the batts exposed, I checked the voltage of each batt and found no more than .01V difference. Guess this really needs to be done on the road under full load.

I can make a bank charger for a fraction of the cost of new batts, so may try this first to bring them back to life. Even if this doesn't work, I can use the bank charger on my new batts.

Also, I cant find 38Ah batts in this dimension...H 160mm, L 195mm, W 130mm. They're all larger width. Can find max 34Ah in this size. Would I get a noticable difference with these?

Thanks again...Doorframe.

doorframe
Offline
Last seen: 14 years 2 months ago
Joined: Saturday, July 19, 2008 - 13:06
Points: 25
Re: Erato 1500W batteries going down

Please guys...I really need some help here.
I took the plunge and bought 4 new batteries. They are numax 34Ah GEL batteries. I actually ordered Lucas, but the seller (ebay) telephoned me to say he was out of them and that numax are the same company, so are the same battery. He also told me that my original Electier 38Ah are actually 34Ah, as no 38's were made in this physical size.

My problem is that they seem not to take a full charge. Or even half a charge. Using the charger supplied with the scooter, it says they are charged, but the dashboard power meter goes almost into the red as soon as I leave my driveway. I can feel the obvious lack of power immediately. I have managed 4 miles before the controller cuts the power and I have to limp home. I then recharge and ride again, with no improvement. I've done this about 6 times now.

As a test, I re-fitted the old 'worn-out' batteries and got nearly 10 miles, before the needle even touched red. And even then, the power did not cut.

The charger is a 48v 6A and recharges the old ones in about 1.5 to 2 hours. It also takes about 1.5 to 2 hours before it decides the new ones are charged and gives me the green led. From such a discharged state, I thought it would take longer to do this.

Do you think the charger could be faulty, or incompatible with the GEL batteries, or any other suggestions? Maybe this is normal with new batteries?

Please give me some help guys...I'm really getting desperate. Thanks.

antiscab
Offline
Last seen: 10 months 1 day ago
Joined: Saturday, July 7, 2007 - 23:55
Points: 1686
Re: Erato 1500W batteries going down

do you have a voltmeter?

if so, while the batteries are charging monitor the voltage.

for a 48v pack, the voltage should get up to 57.6v.
If it doesn't do this, than the charger is at fault.

Do you have any single 12v chargers?
charge all batteries independantly, then load test them.
Im not sure if you have access to a big load like an inverter or a carbon pile.
at 40A load, they should stay above 12v.

If the new batteries appear to charge correctly, and they fail the load test, then chances are they are DOA.

Matt

Daily Ride:
2007 Vectrix, modified with 42 x Thundersky 60Ah in July 2010. Done 194'000km

marylandbob
Offline
Last seen: 5 years 8 months ago
Joined: Monday, June 22, 2009 - 12:24
Points: 524
Re: Erato 1500W batteries going down

If your batteries are defective, replacing them as a matched SET will give best results! Replacing only one unit will typically result in an unmatched charge/discharge cycle, resulting in overcharge/discharge of some batteries, and undercharge/discharge of the others, resulting in a shorter battery lifespan. Avoid DEEPLY discharging the batteries, and recharge them promptly after use, store them fully charged, and they will be happier and live longer. For best results, purchase a new set of identical batteries, and charge them in parallel, with a suitable charger, before installing them in series inside your vehicle. This will assure that all batteries are charged to the same voltage at the start. (doing this again, every 10 or 20 charges, might help prolong their service life)-Bob

Robert M. Curry

reikiman
reikiman's picture
Offline
Last seen: 12 months 2 days ago
Joined: Sunday, November 19, 2006 - 17:52
Points: 8447
Re: Erato 1500W batteries going down

Bob, that's good advice but I believe he did that. His initial posts certainly sound like he was following the advice you just gave.

It sounds like the replacement cells are bad. But can't tell for sure until you do some voltage measurements. The voltage measurements to do are a) when the batteries are charged, b) under load similarly to the test you described doing.

doorframe
Offline
Last seen: 14 years 2 months ago
Joined: Saturday, July 19, 2008 - 13:06
Points: 25
Re: Erato 1500W batteries going down

Hi..big thanks for the replies...

When charging the voltage across each individual battery does get up to 14.5v, (57.5 across the 4). But, I read on another post that the voltage should go straight up to that level, and then stay there until the current drops to a certain level, and then go to float. The voltage on mine only very gradually rises during the entire charging time, and goes to float within a few minutes of reaching 14.5v. It then drops to 13.5v while on float, and if I disconnect the charger it will settle on 13.1v.

I'm desperately clinging to the hope that the batts are good, and not DOA. The seller promises me they are new stock, and Numax is a recognized quality brand, and surely all 4 can't be bad?

To his credit, the seller has offered (in an email) to take them back and refund me. He has also been good enough to send me a Numax 24v 4A charger on approval. It has an XLR type 3 pin connector, so I have connected a suitable socket across each pair of batts. The first pair has finished charging, and the second is on now. In the morning I'll go for a spin and see the results with a digital volt meter connected. Not sure whether to go across a single batt or all 4.

I'm really gutted about all this. Up till now my Electric Scooter has been the best buy I've ever made. If these batts do end up being returned, the old ones will go back in and and there will be one more scooter on ebay. I will be sorry to see it go.

Cheers.
Doorframe.

antiscab
Offline
Last seen: 10 months 1 day ago
Joined: Saturday, July 7, 2007 - 23:55
Points: 1686
Re: Erato 1500W batteries going down

hi Doorframe,

for charging, the charger profile is:
constant current (voltage will start at whatever float voltage is and slowly rise to 14.4v)
constant voltage (voltage wil be held constant at 14.4v until current falls below some value)
constant voltage (voltage will be held at around 13.8v)

what you describe indicates the charger is not at fault.
since the charge profile looks correct, the batteries are not likely to be at fault either.

have you load tested the batteries outside of the scooter?
i recommend doing this so you can completely remove the new batteries as the culprit.

once this is done, put them back in the scooter, but this time check *all* connections.

Matt

Daily Ride:
2007 Vectrix, modified with 42 x Thundersky 60Ah in July 2010. Done 194'000km

marylandbob
Offline
Last seen: 5 years 8 months ago
Joined: Monday, June 22, 2009 - 12:24
Points: 524
Re: Erato 1500W batteries going down

The voltages you gave sounded good, but were they determined by dividing the voltage of all batteries, or were the batteries measured individually? Individual battery voltages are required to make a determination of their condition. Let us know the results, both immediately after/during charging, and again after discharging by operating the scooter afew miles.(also: check all connections/cables carefully for signs of corrosion, looseness, overheating, damage, or discoloration-this can cause problems!-Bob

Robert M. Curry

doorframe
Offline
Last seen: 14 years 2 months ago
Joined: Saturday, July 19, 2008 - 13:06
Points: 25
Re: Erato 1500W batteries going down

Some results...

The Voltages measured are approx, as the digital meter takes a moment to settle

New Batts....freshly charged....standing at 13.1V

Ride was dull and lifeless from the off.

On flat level road....voltage drops to 11.5V approx

Under load up slight hill....voltage drops to 10.8V approx

Power cuts after only 4 miles. Needle in red on first hill (200yrds from home)

Old Batts....freshly charged....standing at 13.1V

Ride was nippy and responsive for first 9 miles.

On flat level road....voltage drops to 12.8V approx

Under load up slight hill....voltage drops to 12.2V approx

Power didn't cut even after 15 miles, although performance tailed off after 9 miles. . Needle in red only on steep hills after 10 miles.

The old batts were connected using the same wiring loom as the new ones. All connections were checked on new and old. This must prove conclusively that even if the new batts are not faulty, they simply cannot deliver the required current...not even for a short time after a full charge.

Also, there was no difference in performance with the new Numax charger, proving my old charger is fine.

Although my commute to work is only 10 miles it includes a few long steep hills and many stop/starts, and I'm not confident of making the distance now the range has dropped. I can't afford a small fortune for batteries that ultimately won't do the job, so it's "EBAY, HERE I COME!"

Thanks again for your help.

Doorframe.

marylandbob
Offline
Last seen: 5 years 8 months ago
Joined: Monday, June 22, 2009 - 12:24
Points: 524
Re: Erato 1500W batteries going down

You failed to say, but if the 10.8 volt figure was obtained by measuring across just ONE battery, that battery is dead! If it was obtained by dividing the TOTAL VOLTAGE by the number of batteries, you have at least ONE bad battery, and separate readings are now needed to see if all batteries do have near identical voltages at the failure point of discharge. (sometimes only ONE battery develops a problem, and it could drop to very low voltage under use, with the other batteries still having good voltages.)-Can you raise the wheel off the ground, to enable safely measuring each battery WHILE the motor is running? If all batteries have dischaged to less than 11 volts they are ALL dead! If all died early, I would suspect that someone accidentally sent you a set of OLD batteries instead of new, perhaps they got mixed at the store? Some companies do stamp date codes into the batteries, it may be good to check this. If they exchange your batteries, before installing or charging the new batteries, check the voltages of each one, to see if it measures at or above 12.5 volts. The voltages should also be very nearly identical at each battery.--Bob

Robert M. Curry

doorframe
Offline
Last seen: 14 years 2 months ago
Joined: Saturday, July 19, 2008 - 13:06
Points: 25
Re: Erato 1500W batteries going down

Hi...
the standing volts was done individually, but the running volts was done by division of 4, measuring across the pack. I did the "wheel off the ground, with full throttle and full beam on, with the rear brake on just enough to bite without cutting the power" test a week ago, and all the batts were within .01v of each other, so I could not identify a weak one. I know it wasn't 'full load', but it was the closest I could do to measure them individually.

I have re-boxed the batts now, ready for collection, which is yet to be arranged, so I'll unpack one and have a look for a date stamp.

Thanks
Doorframe.

doorframe
Offline
Last seen: 14 years 2 months ago
Joined: Saturday, July 19, 2008 - 13:06
Points: 25
Re: Erato 1500W batteries going down

No Date Stamps...they've been returned now so just waiting for a refund.

Just found some batts on ebay ...Greensaver 36Ah / 10HR

here's a link.... greensaver

Just concerned about the '10HR' bit. Can anyone advise me please?

Cheers
Doorframe

robert93
robert93's picture
Offline
Last seen: 7 years 4 months ago
Joined: Thursday, August 13, 2009 - 12:28
Points: 240
Re: Erato 1500W batteries going down

appears to have been a typo,, I'm seeing SPECIFICATION:
Voltage:12v
Capacity:36Ah

antiscab
Offline
Last seen: 10 months 1 day ago
Joined: Saturday, July 7, 2007 - 23:55
Points: 1686
Re: Erato 1500W batteries going down

lead acid batteries (of which "silicon" batteries are) suffer from peukets effect.
basically, the more current you draw, the lower the Ah capacity is.

the 10Hr rating means capacity is 36Ah if the current draw is 3.6A.

from my own testing, available capacity at around 40-50A will be around 26-27Ah.

Matt

Daily Ride:
2007 Vectrix, modified with 42 x Thundersky 60Ah in July 2010. Done 194'000km

doorframe
Offline
Last seen: 14 years 2 months ago
Joined: Saturday, July 19, 2008 - 13:06
Points: 25
Re: Erato 1500W batteries going down

So, if I understand that correctly, that means that a 12V 36Ah 10HR will not have the range / distance of a 12V 36Ah 20HR. Although the Ah rating of mine is debatable, I think they have 20HR on the label.

Why do batteries have to be so complicated? Surely others have bought batteries for their EV's without these problems.

PS....Robert93 wrote...appears to have been a typo,, I'm seeing SPECIFICATION:
Voltage:12v
Capacity:36Ah

If you click the link, the pic on the right defo says 10HR.

Cheers
Doorframe.

marylandbob
Offline
Last seen: 5 years 8 months ago
Joined: Monday, June 22, 2009 - 12:24
Points: 524
Re: Erato 1500W batteries going down

When comparing batteries, if ampere-hour and voltage ratings are similar, the battery rated for the SHORTER time discharge is the better, more powerful battery, with lower internal resistance! (A battery rated 36 amp-hours at 10 hours is BETTER and more powerful, than one rated at 36 amp-hours at 20 hours)--This means that the first battery, the one with the 10 hor rating, can provide 3.6 amperes for 10 hours, and the 20 hour battery can provide 1.8 amperes for 20 hours. With such ratings, the 20 hour battery would be likely to only provide 3.6 amperes for 9 hours or less. The discharge rate of batteries in you vehicle is likely to be much closer to the ONE hour rate, as would be the case if the current drawn were near or above 20 amperes. (NO, you will NOT get 36 amperes for one hour from a normal lead-acid battery with a 36 ampere-hour rating, because this rating is based on a smaller current, for a longer time!) Consider yourself LUCKY if you could get 36 amperes for 1/2 hour from a 36 ampere-hour rated lead-acid batterty! Nickel cadmium/ nickel metal hydride and lithium batteries ARE often capable of full rated discharge in one hour, as their internal resistance is much less.( a typical vehicle will operate LONGER and go further/faster on a lithium or nickel based battery with identical advertised voltage and ampere-hour ratings, because of this ability of the other batteries to be discharged at higher rates of discharge more efficiently.--Bob

Robert M. Curry

doorframe
Offline
Last seen: 14 years 2 months ago
Joined: Saturday, July 19, 2008 - 13:06
Points: 25
Re: Erato 1500W batteries going down

Bob...I've read it a dozen times now, and all I can say is....That's my 'battery theory' turned well and truly on it's head! I had no idea it worked that way.

I've got a price for 4 now...just need to finalise the deal and hopefully I'll be back on the road very soon.

As a thought...If I bought all 8 and put 4 on the scooter, could I keep the other 4 in tip-top order by a once-a-week top-up charge until I needed them, even if that's a couple of years away?

Also...should I charge each batt individually to balance the pack before normal use, as I've now got access to a 3-stage smart charger at 12v?

BIG BIG THANKS!!!!!

Doorframe.

marylandbob
Offline
Last seen: 5 years 8 months ago
Joined: Monday, June 22, 2009 - 12:24
Points: 524
Re: Erato 1500W batteries going down

Yes, I would separately charge the batteries before installation, and test them after allowing them to sit for about 24 hours after charging, to see if the voltages are identical. As far as keeping extra batteries goes, I would charge them about every 3 months, not every week, and also charge them right before installation. This would keep them near fully charged, without too many charge cycles being involved. Excess charging can deplete water from the electrolyte.--Bob

Robert M. Curry

wookey
Offline
Last seen: 11 years 4 months ago
Joined: Wednesday, April 8, 2009 - 06:12
Points: 90
Re: Erato 1500W batteries going down

Sorry I missed this thread earlier. I expect to be following you down the 'new batteries' road soonish (probably before the winter is out - we'll see). I am planning to take the more complex and expensive LiFePo4 route, but that requires some research.

I have some charging numbers from when my cells were fresh, and some recent discharging numbers, which may be of interest:
My charger charges at 14.95-15.1/batt (which seems worryingly high) during initial bulk-current phase (about 5A, 300W). Later falling to constant voltage at 57.6V, 0.6A. This regime does not seem to have treated batts too badly as they are still in reasonable fettle (somewhat reduced capcity from new) after 3000km (~150 cycles). All cells were measured within 0.1V when new - I guess I should check them again now.

When riding discharge rates peak at about 52A (2.5kW), with normal flat full-speed riding at ~1.4kW (~32A). Lowest batt voltage under load ~41V

Range is always fine coming home from work where batts were just charged inside in the warm. Going to work on a cold morning when batts were charged a few days before can get me right down into the red, around 41V full-load, which I suspect is bad for battery life. (distance is 20km, pretty flat, 2/3rds full-speed country roads, 1/3rd stop-start town riding, typically using 13-17Ah, or 650-800 watt-hours)

Wookey
Sakura s50 (Efun A)

doorframe
Offline
Last seen: 14 years 2 months ago
Joined: Saturday, July 19, 2008 - 13:06
Points: 25
Re: Erato 1500W batteries going down

q

wookey
Offline
Last seen: 11 years 4 months ago
Joined: Wednesday, April 8, 2009 - 06:12
Points: 90
Re: Erato 1500W batteries going down

Did you mean to post more than that doorframe?

My batteries are on the way out too. I've twice now had the controller switch down to low power mode under acceleration for the last few hundred metres of my commute. I've going to have to ride slower once it gets cold, I suspect.

I've started some serious battery research in order to choose which batts to buy. Endless-sphere has an infinite amount of battery discussion to read! So far I favour a pack made from headway cells (definately plenty of current capacity) or Foxx packs (which are nice and cheap but a bit stingy on max amps) (anyone have feedback on those?). I haven't found much info from people who have converted from SLA to LiFePo4, either here or at endless-sphere. Pointers welcome.

I'll post some summary option figures soon.

Wookey
Sakura s50 (Efun A)

doorframe
Offline
Last seen: 14 years 2 months ago
Joined: Saturday, July 19, 2008 - 13:06
Points: 25
Re: Erato 1500W batteries going down

Did you mean to post more than that doorframe?

LOL...had a mad moment with my keyboard, my PC froze, a post disappeared, and I was left scratching my head!

I took the gamble on the greensavers...had no options in the end. They are actually the SP-27... with 27 being the 2Hour rating. I'm using a 12V smart-charger on each first b4 they go into the scooter. Fingers crossed!

I think I got a good deal. 2 sets for £260. Thats just £32.50 per battery. 1 set to use and 1 set to keep topped up and ready. Turns out the guy used to sell leccy scooters and imported these with a consignment. He's still got about 2 dozen (batts...not scooters), sealed and boxed, but reckons they are going fast. He's in SW London.
If anyone wants his number just PM me.

8ping8
Offline
Last seen: 13 years 7 months ago
Joined: Thursday, November 5, 2009 - 16:54
Points: 3
Re: Erato 1500W batteries going down

i got thoose green batteries for sale still in good condition, i also brought the erato scooter. The scooter total milage is 100km it is still new. Im still waiting for my registering papers. My first ride got 48km on full charge, great fun. Im upgrading it to LifePO4, so any offers out there? East London, UK

wookey
Offline
Last seen: 11 years 4 months ago
Joined: Wednesday, April 8, 2009 - 06:12
Points: 90
Re: Erato 1500W batteries going down

That is a good price on Greesavers, doorframe. But I've decided to fork out for Lithiums. I just have to choose some (and fast - my current lto clearly aren't going to last much longer). I need to check the controller parts to see how much voltage tolerance I have. I've like to go to 60V or 72V if it looks like it'll take it, for a bit more voom.

Wookey
Sakura s50 (Efun A)

doorframe
Offline
Last seen: 14 years 2 months ago
Joined: Saturday, July 19, 2008 - 13:06
Points: 25
Re: Erato 1500W batteries going down

But I've decided to fork out for Lithiums. like to go to 60V or 72V if it looks like it'll take it, for a bit more voom

WOW!! I hope you've got a bulging wallet!

antiscab
Offline
Last seen: 10 months 1 day ago
Joined: Saturday, July 7, 2007 - 23:55
Points: 1686
Re: Erato 1500W batteries going down

60v (20 cells) is probably the upper limit.

most "48v" controllers use 75V FETs and 63v caps.
the caps can be easily replaced.

all in all, the controller wont last as long, but you can always upgrade to a kelly once it has failed.

Matt

Daily Ride:
2007 Vectrix, modified with 42 x Thundersky 60Ah in July 2010. Done 194'000km

wookey
Offline
Last seen: 11 years 4 months ago
Joined: Wednesday, April 8, 2009 - 06:12
Points: 90
Re: Erato 1500W batteries going down

I note that my existing SLAs are at about 58V fresh off the charger. A 20-cell LiFePo4 pack would be about 77V off the charger. Perhaps this voltage doesn't really matter as it immediately sags the moment any power is delivered? I will take controller to bits tomorrow to see what voltage is on the FETs and caps.

Re price, yes it's not cheap, especailly if I up the capacity. Favourite options so far are Foxx and headway packs:
Foxx: (3C discharge max - I need 30A running, 50A peak)
48V20Ah £404
48V30Ah £600
60V20Ah £480+extra BMS cost
Headway: (10C max discharge)
48V20Ah ~£500
60V20Ah ~£640

I use 13Ah getting to work, so I assume a 20Ah pack would be sufficent (is that reasonable with lithiums?), although it would be better to have more margin than that for long-term lifetime and ability do side-trips.

No-one in the UK seems to be selling these so I get to order from the US. Anyone know how much duty one gets charged on batteries? - it could be painful.

Wookey
Sakura s50 (Efun A)

antiscab
Offline
Last seen: 10 months 1 day ago
Joined: Saturday, July 7, 2007 - 23:55
Points: 1686
Re: Erato 1500W batteries going down

a LiFePO4 20 cell pack shouldn't be charged any higher than 72v regularly.

absolutely don't run the controller when the pack voltage is above 73v.

by the sounds of it, 20Ah will be fine.

Matt

Daily Ride:
2007 Vectrix, modified with 42 x Thundersky 60Ah in July 2010. Done 194'000km

wookey
Offline
Last seen: 11 years 4 months ago
Joined: Wednesday, April 8, 2009 - 06:12
Points: 90
Re: Erato 1500W batteries going down

OK. I took my controller to bit tonight. Some pics here: http://wookware.org/pics/moped/controller/

In fact it has 100V caps and IRFB4310 which is a 100V part. So this would appear to be an unusual case of Chinese stuff that is not built to the minimum possible spec, and I should have no problem going to 72V should I wish to. This bike came in a 48V and 60V model - maybe they both used the same controller? I'm sure 60V will be fine with this motor; 72V might cause sufficient overheating to be a problem?

Anyone know what the unused wire pads are likely to be for?

Wookey
Sakura s50 (Efun A)

Pages

Log in or register to post comments


Who's online

There are currently 0 users online.

Who's new

  • xovacharging
  • stuuno
  • marce002
  • Heiwarsot
  • headsupcorporation

Support V is for Voltage