I've logged 3,000 miles on a 2006 Emax Sport and have replaced the batteries once after only a few hundred miles, and now they need replacing again. I currently get less than 10 miles per charge. My center stand broke, the turn signal switch doesn't stay on to the right, and I'm weary of fiddling with annoying adjustments and issues. My old 1982 Honda Silverwing is less troublesome. I've listed my Emax for sale, but if anyone has words of advice or encouragement, I'm listening . . .
Randy in Olympia, WA
Randy Let me get you some new greensaver batteries at cost all you have to do is report all your experiences back to this site. The at cost price is 35 dollars per battery plus shipping. I have a set of these batteries in stock.
Eric Fisher siliconebatteriesusa.com
Randy I will be in Washington in 2 weeks. I would like to see you scooter do you still have it for sale.
Eric Fisher
Thanks for the offer of new batteries. Another user also offered me "new" silicone batteries for an even better bargain, but I'm just not sure my EV enthusiasm is still viable, at least not for hundreds more $$$. Would anyone have bought an Emax if this was the sales pitch:
For sale: Brand new, German-engineered electric scooter with eight new technology batteries that are guaranteed to last for 4,000 miles with a range of 30 miles per charge at first with the range gradually decreasing to less than 10 miles near then end. Of course, to get this outstanding performance you'll have to invest in battery equalizers for around $350, which are not included in our bargain price of $2995, and you'll have to replace key components in the two charging units. In fact, you'll probably want to invest in better chargers anyway--maybe you can squeeze 4,500 miles out of the batteries. But you're a pioneer, right? So it's OK. By the way, the new technology batteries will be difficult to find after your maximum 4,000-mile range is up, but regular SLA batteries will probably work better so just get the best deal you can find at the time. Customers report that replacement batteries can be found for less than $500 total. You'd also be advised to replace the rear tire about the same time as the batteries, just for safety. That extra battery weight really wears on the tire more than a gas scooter. While you're at it, replace the rear brake shoes. We should have put disc brakes back there but the cheap Chinese scooter we use as our base doesn't have that feature, and we wanted to bring this bargain to you quickly. Our German engineers didn't really test this thing in real life, so there might be some design flaws. For example, some customers recommend taking the controller apart and gluing down the large capacitors; in fact, go ahead and get bigger caps, just to be safe. We're so convinced that design flaws might be an issue that we will soon sell our business to another group so that we don't have to take responsibility for any problems. We're sorry for any inconvenience our going out of business may cause. ..... blah, blah, blah.
Eric . . . Just let me know exactly when you'd like to check out my Emax. I'm in Olympia, about 60 miles south of Seattle. I'd rather sell it than part it out, but if no one is interested I may sell it piece by piece.
I understand the hobby part of all this, which is really a lame way to justify outrageous expenses, but I understand. I bought a 1982 Honda motorcycle in November, and keeping it up is also a hobby. The difference is that for the Honda, while hard to find some parts, the hobby is manageable and somewhat predictible. I expected nothing more from my Emax than their advertising promised:
1. 29mph or 35mph with speed restrictor removed. (Fairly accurate, maybe 34mph.)
2. 12,000 miles or 2 years battery life. (No owner even comes close!)
3. Parts and batteries easily available from dealer. (No, not even close.)
Are these "expectations" too high?
Anyway, I did leave a PM with my phone number.
I went ahead and got 8 silicone Greensavers from Eric, so I'm keeping the Emax scooter for a few thousand more miles. Eric made a great deal and I'll bring back my progress reports as the batteries age. It'll probably be this Saturday--February 9th--before I get them installed. Any advice out there about getting these batteries ready?
I think that's a good estimate. I'll bet that if the batteries were cared for properly than 6,000 miles is realistic. I hope the newer silicons live up to their life cycle spec. I think you'll have good battery life Randy with bulk charging as usatracy recommends. I've personally observed powercheq units to allow battery voltages to go over 15.5v during string charging so I can't say I recommend using them and string charging, and usatracy I believe has measured the BattEQ equalizer to allow battery voltages to go too high as well with string charging, or not balance as well as bulk charging. I don't have enough information to directly compare string and bulk charging impact on battery life, but I have to side with usatracy in that I agree bulk charging is a safer bet for now. That's not to say equalizers are impractical in use with a string charger to help with equalization and prolong battery life, as PJD seems to be having good experience with them.
Just to give some terrible comparisons since I have not much else atm, a lectra motorcycle owner using AGMs got over 3,000 miles, and the lectra had about half the range (so put about twice as much wear on the batteries per mile). This was using Optima yellow tops which were high quality batteries, but I've heard the quality has since come down. This was charging two strings of two 12v batteries in parallel, for a 24v system.
Another bad comparison is my family's renault electric car. It used 18 Trojan brand flooded golf cart batteries for a 144v system which are very robust and built more like industrial deep-cycle batteries. The batteries lasted 18,000 miles, and the max range was about 45 miles give or take. The batteries were forced overcharged to equalize (which will kill AGMs).
Another comparison is Jacob Oshin's Corbin Sparrow: http://www.evalbum.com/1037 I sent him an email and he responded with:
It's not only possible to get good battery life, but given the proper care, good battery life is inevitable. Batteries, like any other manufactured product, will live up to tested specifications provided they are used under the conditions they were tested under, and the quality is such that the product you buy is as close as possible to that used in testing. What that means is good quality batteries, plus the proper care is almost guaranteed to give good battery life, and I think the above ancedotal evidence is good support of that. That's just my 2 cents, and I think you'll get good results with your new batteries provided these silicon's meet their life cycle specs.
[url=/forum-topic/motorcycles-and-large-scooters/587-my-kz750-electric-motorcycle-project]KZ750 Motorcycle Conversion[/url]
[url=/forum-topic/motorcycles-and-large-scooters/588-fixing-my-chinese-scooter]900 watt scooter[/url]
Pic from http://www.electri
Thanks, Andrew. I hope to extend the battery life (mileage) this time around. Now I have a good 12-volt charger, but what will I need to have the best luck "individual bulk charging" instead of serial charging? I guess I'll need 8 chargers??
I really believe that the GreenSaver batteries are better quality than the original Guining. I'll have a better sense of that in a few weeks, but the real test will be how the batteries are in October.
If he's got 8 batteries, than he can buddy pair them. That's putting each set of two batteries in parallel, than wiring those sets in series with the rest of the sets. This way he'd only need 4 chargers. I think this will work okay, unless there is a significant temperature difference between two batteries in parallel in which case one could be overcharged. Of course, if they are both hot and there is no temperature compensation (which there most likely won't be) than they both can be overcharged.
Posted in thread "Probably the most important post - REPOSTED is this article: http://www.smartgauge.co.uk/batt_con.html which describes how to wire multiple batteries in parallel. It appears from the article that the following will be a sufficient wiring configuration. *Please note:* I did not include fuses or circuit breakers in the drawing which are essential.
B1 to B8: Battery number 1 to number 8. C1 to C4: 12v Charger 1 to 4. I organized the diagram so that the battery numbers would be easy to keep track of since battery 1, 3, 5, and 7 all have their positive terminals to the chargers, and Battery 2, 4, 6, and 8 all have their negatives to the chargers. Additionally, the interconnecting wires in yellow go from B2-B3, B4-B5, and B6-B7. This is exactly how I would setup this system and number code the batteries to keep things organized.
P.S. Anyone is free to take this drawing and edit or add to as you wish and repost. In fact please do.
[url=/forum-topic/motorcycles-and-large-scooters/587-my-kz750-electric-motorcycle-project]KZ750 Motorcycle Conversion[/url]
[url=/forum-topic/motorcycles-and-large-scooters/588-fixing-my-chinese-scooter]900 watt scooter[/url]
Pic from http://www.electri
Yeah, Paul (PJD) has posted a schematic of parallel buddy pairs specifically for the emax, along with how to install three Powercheq devices (instead of six with the default dual-string configuration). I'm considering it with Powercheqs and string charging or without Powercheqs and using four chargers. Does the bulk charging method using four chargers require any special rewiring?
Thanks for all the advice. The new Greensaver batteries came from Eric Fisher (siliconebatteriesusa.com) and he made me a great deal. Also, I got a replacement seat for a good deal from Joe at Pacific Beach Segway near San Diego. Thanks, Joe.
Instead of Powercheqs I'm opting for a single BattEQ device:
staabatery.com
It is only one device designed for four batteries, instead of three separate devices needed when using Powercheqs. I'll have to pair up the batteries in parallel "buddies" unless I want to double the cost for equalizing. In my daily use it is not practical to have four separate 12-volt chargers, so I'll be using the 48-volt string charger, being careful not to over charge. Besides the stock Emax charger, is there a better 48-volt charger recommended?
In a different thread, I think we had some of this conversation about Randy's search for batteries. At any rate, let me post here, as it seems the appropriate place. I'm in a very similar situation to Randy. The Guineng silicone batteries in my Emax died a while back, and like Randy, I'm struggling to justify the cost of getting new batteries after only 655 miles. But I'm stuck without transportation and have little chance of selling it otherwise. (Anybody want to buy a low-mileage Emax without batteries? Seriously, let me know if you do.) My job unfortunately doesn't really allow me time for a hobby, but I seem forced into it in this case. (Given the time, I could probably enjoy it.)
So, I've been planning to buy B&B batteries and ride the bike until I can sell it or become comfortable with the battery situation. I have been reading usatracy's persuasive posts about the greensavers, and that is an option. Like Randy, I would probably string the batteries into buddy pairs and buy a BattEQ. I have the two chargers that came with my Emax, and I have a Soneil charger 48V/3.5A that I was using when I was running my Emax on 4 batteries.
... which brings me to a question. Back when my Guineng's started giving out, I used a multi-meter to determine which of the eight batteries had low charges and I removed them and ran on four batteries. If I only go to and come home from work once in a day, my commute is only about 5 miles, so I didn't really need the 20 mile advertised range. Could I do that again with four greensavers or B&B batteries and settle for a 10 mile range?
usatracy, I saw your post about the PakTrakr in a different thread. Do you have that mounted on your scoot? I really don't want to add more cost, but given that I want to minimize the time and energy I spend on maintenance, while still being vigilant, I'm tempted.
Thanks for all of the helpful posts here.
I don't see why this wouldn't work fine.
EDIT: Just wanted to add, I'd personally recommend the B&Bs, as I've used quite a few of their batteries, and I've been very pleased. I have no experience with Greensavers.
[url=/forum-topic/motorcycles-and-large-scooters/587-my-kz750-electric-motorcycle-project]KZ750 Motorcycle Conversion[/url]
[url=/forum-topic/motorcycles-and-large-scooters/588-fixing-my-chinese-scooter]900 watt scooter[/url]
Pic from http://www.electri
My original Emax batteries were replaced within the first year with BBs. The BBs worked much better than the original greensavers ever did.
I don't really like the "good greensavers" versus "bad greensavers" theory. The argument flows logically, but it leaves me with a very uneasy feeling. Why chance greensaver 2.0 when 1.0 was such a disaster? I know BBs work and have worked unchanged with the same design for a number of years.
--
davew
"we must be the change we wish to see in the world"
DaveW - Greensaver 1.0 was never actually a Greensaver. It was a complete rip off. Greensaver 2.0 is not being sourced through the same, lovable, wheeler dealers who bought us GS 1.0. GS 2.0's are coming straight from Greensaver.
I just ordered 5 from Eric at siliconebatteriesusa.com - Should be about $500 delivered to my door in about 6 to 8 weeks time.
However - there are certainly more folks using BB's and they do have a good reputation. I think the GS's are better and I'm prepared to take a risk (I bought an XM2000 didn't I?)
John H. Founder of Current Motor Company - opinions on this site belong to me; not to my employer
Remember: " 'lectric for local. diesel for distance" - JTH, Amp Bros || "No Gas.
Thanks for the thoughts on B&B vs. GS batteries. I'm still on the fence for the moment. I'm a bit like Andrew and Davew in that at this point I'm inclined to go with proven technology. Against that, I ride through the winter, so the improved performance of silicone batteries in cold weather is attractive (assuming its true).
I am heartened that it sounds like I might be able to run on 4 batteries again. It sounds like I'm dating or something but ... I've been hurt before, let's go slowly. If four batteries work out, and I can establish that I've got a stable setup and if I find I NEED to go farther than 10 miles, then I can add additional batteries. If anybody has reason to believe that four batteries is a bad idea (5-10 miles per day draws those batteries down too severely?) let me know.
Also, if I only go with four batteries, I don't believe I will need any power equalization devices and I can use the Soneil 48V / 3.5A charger that I already own.
I don't think that's true. If you use a string of SLAs (GS's, BB's or anything else) and a string charger you need to consider equalizing devices. If you use a string of SLAs and bank charge them (i.e. individual charging) then you can probably pass on equalizing devices.
I'll keep folks posted as to when my GS's turn up and my experiences with them.
John H. Founder of Current Motor Company - opinions on this site belong to me; not to my employer
Remember: " 'lectric for local. diesel for distance" - JTH, Amp Bros || "No Gas.
Yeah, while that's a decent idea to have power equalization devices I don't think it's an ABSOLUTE MUST REQUIREMENT to have such things. But if you don't it's a good idea to regularly check the individual charge and if the pack becomes unbalanced to take action such as doing some individual charging. Pack balance is primary importance and there are several ways to achieve it.
- David Herron, The Long Tail Pipe, davidherron.com, 7gen.com, What is Reiki
Reducing the number of batteries in a string does not mean you can do away with balancing. This is a very important process and if you do not use some type of balancing the batteries will suffer.
I personally think bank charging is the best way to balance your batteries. I have had PowerCheqs on my e-bike and they worked great but had to be disconnected when the bike was not in use of more than a few days. I have also used bank charging on the same e-bike and found the batteries lasted much longer than string charging. I have removed the PowerCheqs and will return to bank charging on that bike as well as change all my other bikes to bank chargers. I have 2 "Battery Tenders" on my boat and I plan to purchase more of these little charges to use as bank chargers for my e-bikes.
Chas S.
Sorry, I think I forgot to mention in my previous post ... and I should really phrase this as a question: Can I wire four batteries into two buddy pairs and thus at least decrease the need for balancing (the same approach as rewiring 8 batteries into four pairs). I'm guessing the answer is that you still need to balance the two pairs?
If I go with bank charging (4 Vector chargers probably), how are you guys doing it? Do you uncover the batteries each time you need to charge and then attach clamps to each battery? Or do you wire up plugs that can be easily tucked up somewhere until you're ready to charge?
Thanks for sticking with me on this.
The little charges I use are 1 pound each so I just leave them in the bike and connected through a 120 volt AC relay. I bring all the 120 volt AC connections together including the relay coil and put 1 connector on the bike to power everything. When the 120 volts AC is connected the relay is energized and the charges are connected through the relay contacts to the batteries allowing them to charge. It takes more than 1 relay but they are only on when the 120 volt AC is connected.
Most people just put connectors on wires they can connect to when charging.
Grandpa Chas S.
e-commuter,
You need at least four batteries in series. in the parallel-pair ("buddy pair") scheme, eight batteries are used in order to effectively obtain four batteries of twice the capacity. This means if you have only four 20AH batteries, no parallel-pairing is possible or you will get only 24 volts.
If you use battery balancers, bank charging isn't really necessary. But you should check the indicator lights on the balancer module every few charges to make sure it is continuing to operate.
PJD, thanks for setting me straight on the buddy pair proposal. Sounds like I would need to have three powercheq devices in order to balance the four batteries. It would work out less expensive then for me to buy four smart chargers. (Would 2 amp chargers be sufficient? I wonder how long it will take to charge a battery.)
Chas, I'll probably start simple and just have wires attached to the batteries, especially since I plan to only use four batteries. However, I am going to keep your setup in my back pocket. I like to have things neat and organized if I can.
Chas - those Battery Tenders only put out 0.8 amps - seems too small to be a viable charging solution. I'm using the smallest Vector charger that outputs 2 amps (but I'm still thinking of ditching them because I'll need more current).
John H. Founder of Current Motor Company - opinions on this site belong to me; not to my employer
Remember: " 'lectric for local. diesel for distance" - JTH, Amp Bros || "No Gas.
I guess one other consideration for me in deciding about bank charging vs. string charging is my daily routine. Most days, I will ride to work (a short distance of 2.5 miles), maybe come home for lunch, then back to work and home at the end of the day. Most of the time I will not come home for lunch, and the scooter will be sitting outside under a covered parking area for anywhere between 4 and 8 hours. Do I need to be charging during the day to maintain battery health or will an overnight charge-up each night do the job? I might be able to carry four 2-amp vector chargers with me (a bit bulky I would imagine), and if I use Chas' method to consolidate them for one plug-in-socket, I could still bank charge, but I won't be able to find 4 sockets otherwise (I suppose I could carry a power strip). I could string charge with my single Soneil charger if I spring for the 3 powercheqs to balance 4 batteries.
To determine how long a CC-CV type charger takes to charge a battery, divide the AH of the battery by the amperage of the charger then multiply this by a factor to account for the tapering amperage in the CV stage - 1.2 is a good number. So your 2 amp chargers will take about 12 hours to charge your batteries when they are fully depleted and in good condition.
However, in actual use you will not actually deplete the batteries fully because of the high rate they are discharged (Peukerts effect), so I'd guess they will normally charge in no more than about 8 hours.
SLA'a should not normally be charged at more than 0.3C except occasionally. So a good size charger would be 6 amps.
As far as when to charge, the answer for all lead acid batteries is as often as possible. So the up to 8 hours that the scooter is sitting partly discharged is shortening the life of your batteries at least some amount. You vcan minimize this effect by keeping the scooter in as cool a place as possible in the warm season.
e-commuter,
It would be best to charge your batteries during work hours but I would NOT recommend using a string charger. A string charger will not keep things balanced and defeat the work of the bank chargers. I think you would have less damage to not charge than to use a string charger. (IMO)
John,
At .8 amps it takes 7.5 hours to charge a 12 AH battery that has a 50% discharge on it. In other words .8 amps puts out 6 AH in 7.5 hours. I rarely use more than 8 AH when riding the bike I have this setup on. 8 AH will take 10 hours to fully charge. So overnight charging works just fine. The only time you need more amps is to charge faster so you can ride more than once a day. When I want to do that I use a large 35 amp charger on each battery for the required amount of time. In the case of 6AH I would leave the the charger on for no more than 10 minutes. I use a Cycle Analyst meter (DrainBrain) to let me know how many amp hours I have used during a ride.
Grandpa Chas S.
Chas,
In your previous post, I believe you said that you have your chargers on board your bike (thanks for describing that setup). Are they within the body panels of the bike? Do you not have problems with them overheating in a confined space?
The bike or I should say Trike is a Delta semi recumbent 3 wheeled bike. I have lots of space between the 2 rear wheels. These charges are sealed and water proof so they are designed to operate in a closed environment, and I have never had a heat problem.
Chas S.
I know this is an old, perennial argument, but I am of the opinion that if battery balancers are used (with occasional checks of the indicator lights for proper function), then I think string charging is fine. It is also simpler, convenient, and more elegant way to charge.
That's how we will be charging our 16-cell LiFePO4 packs (with the help of a BMS for balancing)
BTW, Have you gotten any advance copies of the Gary and Bob BMS kits yet?
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