Replacing SLA batteries on E-bike

[samenameall]

Hello, I have some questions about replacing my E-bike sealed lead acid batteries. My E-bike had 48V 20AH batteries (4x 12V 20AH batteries connecting in series) and I want to replace them with 48V 12AH batteries (4x 12V 12AH batteries). My controller needs 15A I think because I see the numbers 250V / 15A on the external battery box. So my questions are:

1. Can I use SLA batteries designed for PC UPS or I need batteries that the label on them saying “electric vehicles” (the old batteries i had on the label it was saying “electric vehicles ”). Most SLA batteries I see for sale doesn’t state something like that.

2. Let’s say we have this random 12V 12AH SLA battery:

- Brand: Ultracell
- UL 12 – 12 (12V-12AH/20HR)
- Rechargeable VRLA Battery
- Constant voltage charge
- Cycle use: 14.4 – 15.0V
- Standby use: 13.5 – 13.8V
- Initial current: Less than 3.6A
- Caution: Do not short circuit

What I need to check on a SLA battery specifications to make sure it’s compatible with my E-bike 15A controller so I can make my 48V 12AH battery pack?

3. The charger I used for my old 48V 20AH SLA batteries is:

Pb-acid Battery Charger
Model: DZM4820
Input: AC220V 50/60Hz
Output: DC48V 3A

Since the output of the charger is DC48V 3A i quess i can charge batteries that have a total of 48V and initial current 3A and less? What types of SLA batteries I can charge with it or what to check on new batteries to know if I can use the same charger?

 

[999zip999]

Lead is dead. Where do you live ?

 

[Telemachus]

Lead is dead.

LOL, lead still powers more autos/bikes than Lithium will in the next 2 decades.

Honestly, 12V 12AH is 12V 12AH. Just purchase from a place with a decent warranty and don't push your batteries too hard.

with prices like this:

https://www.apexbattery.com/search/result/?q=12ah&page_num=6

You could get a whole new set of batteries for $60 every year... and rely on the warranty for that entire year for replacements.

 

[999zip999]

You may get 7ah out of 12ah sla in 2 weeks. Find out the price and compare before you buy a battery.

 

[999zip999]

Those are cheap batteries wonder how good they are ?

 

[Telemachus]

Those are cheap batteries wonder how good they are ?

Apex? They are crap, just like any other SLA. If you drain them down too much a single cell can get a "polarity reversal" and kill the whole battery. And possibly explode.

But how many SLA disasters have you ever heard of?

Apex is close (Vegas), cheap shipping, and extremely decent customer service.

I bought 8 Apex batteries for my kid's bikes. They ride their Pocket Mods daily, so we have been through at least 80 cycles. They don't have the power they did, but the still run.

One of my sets is on it's way out the door. I emailed APEX with the problem, and they got back to me within the day.

When they die, you provide evidence of that to APEX (just take them to automotive store and snap a picture of the battery with 0 cranking amps) and provide that photo to Apex. They give you a BRAND NEW BATTERY any time in the year after purchase.

And they provide you with the return shipping label!

Some of their batteries have 24 month warranties:

https://www.apexbattery.com/apex-apx1280f2-12-volt-8ah-sealed-lead-acid-b.html

 

[999zip999]

Sla need user's guidelines that must be followed for long life. Charge and keep fully charged 13.6v all the time.

 

[samenameall]

So from the responses I got so far my answers to my questions are:

1. I can use PC UPS batteries to make my E-bike battery pack.

2. This random SLA battery i mentioned can work with my E-bike 15A controller and i can make a 48V 12AH battery pack with them because the only factor I need to check is if the battery is 12V 12AH and nothing else in specifications like:

- Cycle use: 14.4 – 15.0V
- Standby use: 13.5 – 13.8V
- Initial current: Less than 3.6A

3. No answers for this question yet about my charger and what types of SLA batteries i can charge with it.

 

[dustNbone]

The charger should be fine, as long as the pack voltage is the same as the old one, which seems to be the case. They're the same type of battery, only smaller in capacity. They will just charge (and discharge) faster than the old ones.

 

[AussieRider]

G'day Samenameall, welcome to ES.
I wouldn't go from 20Ah down to 12Ah. See, the more current you drag, the less SLA will give. You can get 1 amp for 12 hours but you won't get 12 amps for 1 hour. If your controller draws 15 amps, expect about 40 minutes run time, maybe 30 before you notice sag. With 20Ah batts, they don't work so hard, won't sag as much & will last longer. I think it's called the Peukert effect.
Your charger should be ok though it's a tad high for 12Ah at 3 amps. 1.5 to 2 amps would be ideal. You might notice the batts get slightly warmer than the 20Ah did.
Hope this helps you.

AussieRider.

 

[999zip999]

It will work and you must peddle start use only 3/4 of battery and charge as soon as batteries are cool and keep fully charged when not use. Do nit store with low battery voltage. If used over it's rating will ware out fast . Don't know quality of apex.

 

[999zip999]

Ok I can't recommended a style of SLA battery for a 15 amp controller for an e-bike. Starter or deep cycle or ? They are different. How often and how far do you use ebike ? Can you charge at destination ? Plus where do you live ? It makes a difference. They are other plug and play batteries. It depends on how far you like to go ? Plus hills and weight.