I may have murdered my a SLA :(

Discussion in 'Electric Bicycles' started by ozzyu812, Oct 5, 2008.

  1. ozzyu812

    ozzyu812 Member

    Its says in the owners manual, "Never charge the batteries for more than 24 hrs." Which I wasn't it was closer to 9 hrs. But I got the bright idea of putting it on a outlet timer to reduce the time its on the charger after its charged. Now it has about 66% of its range. It has about 150-200 charges on it. The manual says it should be good for 300. It could just be a sign its coming to the end of its natural life.

    What do you think, its showing its age or did I wound it with the timer?
     

  2. skyl4rk

    skyl4rk Guest

    If you have a smart charger, there is no problem. If not, how many amps is your charger?
     
  3. ozzyu812

    ozzyu812 Member

    input: 1.5A
    output: 24v 1800mA

    its a currie e-zip so i would think its a dumb charger lol
     
    Last edited: Oct 5, 2008
  4. SirJakesus

    SirJakesus Guest

    Considering that you push the limit of your bike on your commute at around 12 miles of heavy throttle and no recharge at work i'd say the SLA's have just had enough. I'd say buy a complete pack from currie and some replacements for your current pack and only discharge each of them as much as you need to. I have both packs on my ezip so to go easy on the batteries I always switch over to the alternate battery when I'm at the half way point of my trip. As an added bonus I don't get as much voltage sag and the less I deep discharge them the more cycles they'll last.

    Or.. you could use this as justification to upgrade to a better battery chemistry and more voltage. You know you want to deep down inside :)
     
  5. ozzyu812

    ozzyu812 Member

    I do recharge at work. On the way to work I don't use up much of the battery. I take a break 1 mi away and there is a hill after that point. So I switch to the 2nd battery to have a full charge to take it on. On the way back at the halfway point there is a monster of a hill. Before I take that one on I switch to the 2nd battery. Then leave it on that one the rest of the way. When I 1st got the bike I wanted to test it so I ran it with minimum pedaling and ran out of juice half mile away from the end, uphill all the way. That was the only time I really abused it.

    Well anyway, I'm definitely upgrading to 10Ah24V LiFePo4 batteries from Cyclone . Its just such a better value 2400 cycles for $400 vs. 200-300 for $100. That's about 2-3x more cycles for the money. Not to mention extended range which would reduce the number of cycles needed. I think I actually got about 150 cycles out of it, but it still has some life in it. I don't think the wife can object too much since she spends $400 a month on gas, payments and insurance on the SUV! Don't get me wrong she is usually very supportive in my endeavors.

    Plus I can use the remaining SLA to power a killer light!

    I not entirely sure how this will play into my ultimate goal of a 1500W Cyclone motor. The Cyclone site says its to be mated with 10Ah48V LiFePo4 batteries. I know that if I run 2 10Ah24V LiFePo4 batteries in series the voltage will double to 48V. But what about the Amps? Do they double also? I wouldn't want to fry it due to double the amps. It been a long long time since I studied OHM's law. LOL
     
    Last edited: Oct 7, 2008
  6. abudabit

    abudabit New Member

    Running batteries in series adds up the voltages. Running batteries in parallel adds up the amp hours. Don't run them in parallel though unless you know what you're doing.

    Keep in mind though that it's watts that are doing the work. Watt hours are volts x ah. So 48 v of 10 ah is double the watt hours of 24 v of 10 ah. That's double the potential energy.

    Also keep in mind, lithium have their own delicacies that must be paid attention to. Most likely your sla's died because you were discharging them too much (just discharging them to 50% dramatically reduces life cycle). Lithium's don't have THAT problem, but they have other problems.
     
    Last edited: Oct 7, 2008
  7. ozzyu812

    ozzyu812 Member

    I was concerned about that statement. Then I went to endless-sphere where I had just asked, what BMS meant. I'm such a NOOB! Dogman not only told what BMS was, but explained its function. That put my mind at ease about your warning that Lithium's have other problems.

     
    Last edited: Oct 8, 2008
  8. SirJakesus

    SirJakesus Guest

    When you get the cyclone we'll see if you can keep up with me! Mwhahaha! :)
    Shame about the SLA's though. Are you planning on building another bike for the cyclone or are you going to find some way to mate it to your ezip?
    Personally if I wanted to upgrade the Trailz I would switch out the motor to a larger geared one, change the controller and pack the battery enclosures full of any type of better chemistry and wire them to run from both packs at the same time. I think currie kinda messed up with the 3 position switch, both batteries should be running in parallel all the time on those bikes to reduce sag and to keep you from discharging one battery too much while having a full one on the other side. JMO. I'll be interested to see what you come up with in any case. That 1500w cyclone will really move though if the 400 watt currie motor can move all that weight comfortably to 18mph.
     
  9. ozzyu812

    ozzyu812 Member

    Wife says no Lipo :(

    Wife says no Lipo, for now anyhow. It has to wait til income tax time. So I'm have to settle for another SLA :cry: Its goin to be a waste of money in the meantime. :-x

    I've been thinking about running the batteries in parallel, now that you mention it. From what guys at E-S said, the controller controls the Amps. If I fry the stock one. Oh well, then I'll just run a switch. As I've been meaning to do. It just isn't powerful enough to warrant a controller.To Hades (kids study your Greek mythology) with all the junk wiring in the rack. The smart thing to do would be to test the switch set-up 1st. If I burn up a motor I have a spare!

    The plan was/is to get the 10Ah 24VLiFePo4 batteries, then get a 2nd set of the 10Ah 24VLiFePo4 batteries & finally the Cyclone 1500w motor. Running the 10Ah 24VLiFePo4 batteries in series to equal the 10Ah 48VLiFePo4 battery pack. With the added bonus of having 2 BMS's and 2 chargers. All the while working on putting that 2nd Currie motor on the front sprocket. I may even wind up putting BOTH Currie motors up front. I'm designing the mount with that in mind. This http://www.endless-sphere.com/forums/viewtopic.php?t=4936#p73522 insired me to put them both in the front, eventually. I wonder if he had the same problem I had and got free motor due to miscommunication.

    When I get the thing set up the way I want. It will so more that keep up with ya!! BBUUUUUUZZZZZZZZZZZ!! LOL! Can your goose or Next do 50 Mph?
     
  10. abudabit

    abudabit New Member

    Remember, good chargers save money in the long run. One of the best electric investments you can make, and they aren't really expensive anyways. Get a slow charger, too, at least for SLA's.

    Also charging each individually (one charger per battery) is a very very good idea for SLA. I use DPDT switches to switch between charge mode and run mode. If the switch also has an 'open' position that is good too.

    And keeping your charge above 50% will extend life a lot, and keeping it above 70% will really extend the life of the batteries.
     
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