UGHHH...Now my SLA Batteries are dying!!!

Hi pchech - what's your usage pattern? i.e. how long do you ride? what amps do you draw? Also, do you use battery balancers? My guess is there's something about your situation that is giving you bad luck with batteries - it might be that there's something that can be changed so that you're not having to replace batteries four times a year!

John H.
Blue XM-2000
Ann Arbor, MI

From the above link you posted:

Discharging:
- Highest Discharging rate for continuous running: 10Amp
- Max. Discharging rate for short time: 15Amp

No they won't because they can't handle the discharge rate.

Please read my last reply on this thread: http://visforvoltage.org/forum/batteries-and-chargers/1570#comment-6870 do you have all or any of those accounted for?

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Avatar taken from http://www.electricmotorbike.org/
My KZ750 Project: here

Hi pchech - if you fit powercheq's - or take it to a shop and have them fit them - then you might get much closer to the "maintenance free" life you aspire to.

Don't give up yet, you're real close now...

John H.
Blue XM-2000
Ann Arbor, MI

pchech sorry about your battery problems. You may be right about battery technology. But chances are your scooter setup is just abusing the crap out of the batteries on charging. Its bad engineering. Every EV sold with VRLA batteries should have a battery balancing system unless it is running a very low system voltage. I don't mean offense but to just throw on a new set of batteries and expect them to last long after the old ones failed prematurely is shortsighted. And then to come here saying battery technology is bad just doesn't sit well with me knowing all that went into battery development.

Batteries like any other product of human technology is imperfect and has its operating tolerances. If you exceed the operating tolerances than expect failure. If you do nothing to correct the root problem and just replace the equipment than it will fail again. Do some research and do something about it and use a few of those 100 billion neurons. Or do nothing and expect technology to solve your problems.

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Avatar taken from http://www.electricmotorbike.org/
My KZ750 Project: here

pchech,

What brand and model of battery did you use? There are a lot of cheap, unreliable batteries out there. Since the e-max uses eight batteries, and the failure of just one can cause problems, you have to buy batteries with a good Q/C reputation. Also, rearrangement of the pack into "buddy pairs" and the use of battery balancers (powercheq's or other) is pretty much mandatory. I only trust BB batteries myself.

I have about 2000 miles - about 220 charge cycles - on my BB EB-20-12 pack with powercheqs, on my e-max, and they are performing fine.

:(
Sounds like the same problem I had a a brand new set of `
B&B EB12-12 10AH Batteries but I wasn't able to go 2 miles before they started slowing me down.
The best answer I have is I damaged them by not charging them properly. The proper voltage would still be there, but I had no power.

I just started all over again with a new set of CSB-Battery EVH 12150 and this time will handle them better.

Check out the copy of THE VIRTUES OF IMPEDANCE TESTING OF BATTERIES in our EV DownLoad Library.

Peace Out,
Gman

What is your vision for the future our growing community?

I would concentrate your suspicions on the first or last battery in the string.

` :?

pchech
Odd thing...when I limped home on the drained batteries and then hooked up the charger, the charger registered a full charge (green) in just under an hour charge time?

Mine were doing the same exact thing, I even did a seperate 12 volt charge on each one, and still no change.
I took the Hub Motor apart thinking it was a bearing or bad Hall Sensor, checked the brakes and everything I could think of. Once I over inflated the tires, and it seem to improve on speed, but the range was still less that 2 miles. I had to start carrying both 48 Volt containers just to go a couple of miles.
Since the B. B. Battery Limited Warranty states above 80% I can't return them because they always read above that, even if I can't move a all.
T do plan to take them to a actual local Battery Mfg in business since 1919, where I purchaed a replcement set, and ask them to check them out for me.

Peace Out,
Gman

What is your vision for the future our growing community?

In retrospect, I was very naive when I thought that getting an electric vehicle would be virtually maintenence free? The more I get into this subject the more I regret my purchase. Hey, I love riding the Emax (as much as one can whizzing along at 27 mph) but all this discussion about battery technology is beginning to make my head spin.

This is a very good point and one I try to make to anyone before buying an eBike or an eScooter. My shorthand for this is anyone considering the purchase of one should own and know how to use a socket wrench and a voltmeter. Unless you are one of the lucky few who live within striking distance of an expert you will be doing your own maintenance. Forums like this one are an excellent source of information, but it will always be your knuckles getting scraped.

Electric scooters do require maintenance. Due to their simplicity it should be much less than a gas-powered scooter. Due to remote and badly managed assembly, mediocre design, and aggressive cost reduction they require much more than they should. Selling an electric scooter without a comprehensive battery management system is simply irresponsible. It is akin to selling cars with a leak in the gas tank. People gasp over the $11k price tag of the Vectrix, but this is probably a closer to what it will take to make a reliable, low-maintenance electric scooter. Perhaps a lesser performing scooter could get down to the $5k or $6k range. Asking for a $2k or $3k scooter to be low maintenance is not currently feasible until we get much larger production scales.

This being said, not only are gas powered scooters and motorcycles noisy, obnoxious, and environmentally evil, they are not low maintenance either. One of my friends acquired the nickname "slick" from the number of times he has left his oil in a mile-long streak behind him. The difference is that there is usually a shop within pushing distance to get your stinking gasser back on the road.

I believe in electric transportation and encourage everyone to consider it. However, I believe it is our duty to make sure people go into it with reasonable expectations.

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"we must be the change we wish to see in the world"

pchech,

Actually a bad battery or batteries will cause the short charge time. The charge time for a pack that runs down after just 5 miles will be the same time as a good pack that was ridden only 5 miles. Energy in = energy out.

Question:

is your e-max in the stock battery configuration?

If it is, a bad "black box" can cause only one of the sub-strings to charge. Or, if one of the two main relays is stuck open, you will be riding on only one of the sub-strings - plus you black box will get damaged from the other pack trying to discharge through it.

The bad black box and/or relay is easy to check. The voltage measured at the charging receptacles on either side of the scooter should be the same, and when charging on one side, you should see a voltage rise on the other. The relays should be checked - each should produce a good "click" and you should verify the circuit closes by disconnecting the big battery wire to them and using an ohmmeter to verify they close with near zero resistance.

The easiest way to find a bad battery is to run the scooter down to stumbling, quickly remove the seat (have the four nuts removes before hand) then, with the lights and turn signals on, check the voltage of each battery. The bad battery will have a distinctly lower voltage. When charging, this battery will usually exhibit a distinctly high voltage, or if you are using powercheqs, the two either side of this battery will have their red lights on a disproportionate amount of time.

If you haven't done so, switch your batteries to the buddy pair arrangement, and get battery balancers.

As far as the economics, even the best SLA pack will probably have to be replaced every 7000-8000 miles, So, compared to a gas scooter, it is, at best, a break-even situation. But, for me, it is about pioneering a cleaner low-impact transportation not economics.

Pchech,
What's the name of that book you found?

kringle777
Red XM-2000
Moss Green "Charger" ebike
Sacramento, CA