SLA (Sealed Lead Acid) Battery Safety

kmxtornado

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I'm new and fairly overwhelmed with electronics in general. I've owned a mini e-bike (see avatar) for a few years. It's powered by two 12v batteries for a total of 24v. I know the throttle has lights and is 24v max also. Not sure about the motor size. The controller's maxed at 30A. A few questions about taking care of SLA's. Mind sharing some insight on these bricks?

1. How often should I be charging them?
After every ride? And should I be charging them every 2 weeks at least (in the case that I don't ride for long periods of time? Is that even okay?)?

2. Charge it for how long?
Turn it off immediately when the green light turns on indicating full charge? Slightly longer? Keep it charged all the time?

3. Do I need to watch it while it's charging?
...or at least keep an eye on it in the same room?

4. Temperature?
I charge mine in the garage where it's slightly colder than upstairs. Is this good? Bad?

5. How often should these be recycled and replaced?

Does that depend on how much I use it? Number of cycles/charges? Or should I be looking for some signs of it deteriorating?

6. Any other recommendations?
Absolutely no-no's? Please share as much info as you can about safety of SLA's. Thanks guys!
 
1. After every ride and asap. Lead acid batteries last much longer when they are fully charged.
2. Keep it charged all the time if possible. That is assuming that your charger will switch into trickle charge mode when the battery is full. Most chargers are that way.
3. No
4. Lead acid batteries like warmer climate. But if you always keep them fully charged, it does not matter much. Garage is fine.
5. Depends on how you use them. Two main factors for long life: A) Never discharge below 50%. In other words, whatever the battery capacity is, use only half of it, stop and recharge. B) Recharge asap after use, and keep them fully charged.
6) Can't think of one.
 
Charge lead often. Do NOT let it sit discharged, charge after every ride. Aside from that, it won't matter much.

They will perform better when warm, but they like near (but not below) freezing temps. Store them in cold temps at full charge. Top off every few weeks or month, don't let them go below freezing.

You replace them when they stop performing, which for lead can be rather quickly. It's a really safe battery and you can just about do anything you want with it without issue. Improper use just means short life, unlike LiPo which can mean fires.
 
You guys are awesome!...and so fast! Thanks so much. I'm charging my SLA as I'm writing this. Just gotta remember to unplug it before I go to sleep. I think it's going to be in another hour or so. Glad to know SLA's are fairly safe. I'm reading the LiPo version of this thread now, http://www.endless-sphere.com/forums/viewtopic.php?f=14&t=9170&start=0 for my future setup.
 
1-5: What they said.

6: Don't drop them on your foot. ;)

Also, don't charge them at a significantly higher current than they're rated for by listing printed on them. Can be bad juju as they boil their electrolytes off. :(
 
lester12483 said:
People should stop using sla batteries for ebikes. They are simply too heavy.
Unless you are going to start giving away lithium batteries there will always be some who will start with lead due to its cost and availability.
Sure its heavy and sags badly but for some people its a good start to dip their toes in the water before committing a significant amount of money for a real battery.
For short range low power bikes its may meet some peoples needs, not that i would reccomend it.
 
Yes, I agree they should stop using lead. As soon as their use of the bike justifies the cost. You can get years out of lead, if your needs are a two mile ride to work daily for 3 months each year. For four miles a day, you can easily put up with the weight. So if you can expect a year or two more out of your lead, what's the hurry?

But a 5 ah lipo pack weighing 3 pounds instead of 30 is exactly what you should replace your lead with for that very same use.

That little pocket bike would run great on one single $60 6s lipo pack.
 
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