how to preserve sla batteries

V

videomandw

New Member
hello,

i built an ebike cruiser with three 12 volt 12 ah sla batteries. i want to make them last as long as possible. can anyone answer any or all of these questions:

1. is it true that you should always keep them on charge 24/7 even thru the winter months when the bike is being stored?
2. do battery "conditioners" really work or are they just worthless gimmicks?
3. how many months or years should an average sla battery last under normal conditions (i realize there are lots of variables in this question)
4. is it true you should never ride your ebike until your batteries are completely discharged or is that just a myth?
5. any good tips on how to make your sla batteries last longer.
6. any recommendations where to purchase quality sla batteries at a good price?

thank you for any input
videoman
 
SLA batteries very much like to be charged as much as possible - it prolongs their life. That doesn't mean overcharged , because that usually can kill them - so you need "smart" charger (one that measure temperature and have voltage/amperage sequence - of course , it comes with a price), or you can (as many people do) charge and balance them individually , with personal monitoring of the process(some measuring equipment is needed). Also , you don't want to discharge them more than 50% of their rated capacity , because that reduce number of cycles too .
Battery conditioners: some work ,some doesn't. Unless you know exactly what is wrong with battery (sulfur on the cells , distorted cells , bad electrolyte (poorly conductive)...) you can't use magic wand to cure everything. Anyway , it can cure the first problem (sulfur) , others can't - it's a gamble and depends on luck sometimes - nobody can guarantee that it will work (or claim the opposite).
Battery life depends on many factors , so , if you treat them well , for quality one you can aspect to meet their rated number of cycles (months and years has nothing to do with that - but , you should count for at least two years, with frequent use of the bike, maybe more ).
Question 4. & 5. - read the first part of the post
Question 6. - really , there is no universal good price or quality; you should read (on the internet) whatever you can about the subject , to become capable to decide properly (depends on many factors).
By the time you "wear out" your batteries , you will be considering switching to Lithium based batts. Yes , they are more expensive(at first look , but when you count in time of their service - it is cheaper) , but incomparable with SLA in terms of power , weight , number of cycles , duty life and everything else...
 
When I first started with Ebikes I read that anything over 13.25v is considered a full charge. Anthing under 11.75 is a battery that needs to be charged immediately. I have never been able to use a battery below 12.50v effectively. Most controllers have a built in shut off to keep you from running the battery down too low to recharge.

Keep the sla charged at all times. Do not store it on a concrete floor in the winter. I guess that is because they might freeze I really don't know.

I use three battery tenders one for each battery. There were under 20 bucks each from walmart. I blew up more money trying to use the 24 and 36 volt chargers that come with scooters.

My sla batteries last about a year. I would like to make them last longer. I have not used lithium batteries but the sla has a better power distribution system than the nimh I am playing around with. My next set might be marine batteries with a wet system. I carry them in a trailer anyway so the problems with strapping them on a bike don't really apply.

You can ride the bike until the controller shuts down the bike without any damage but trust me you probably won't unless you live in a pancake flat area. In my case 12.5 is as low as i can get it without wearing myself out.

keep them on a battery tender when not in use and they will last about a year or so.
 
Get a timer-controller that plugs in the wall and plug your battery charger into the timer. Set it to charge for 2 or 3 hours per day.

Another option is to use a small solar panel and charge controller, but that starts to get expensive.

Batteries like to get a small charge each day, even when fully charged.
 
skyl4rk said:
Get a timer-controller that plugs in the wall and plug your battery charger into the timer. Set it to charge for 2 or 3 hours per day.

Another option is to use a small solar panel and charge controller, but that starts to get expensive.

Batteries like to get a small charge each day, even when fully charged.
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For best results with SLA.....

NEVER go below 80% DOD (= 12.00v) If you do go to 11.85 and below, you start getting sulfated batteries, in which you will see a decrease in range.

Always Keep it charged. If you've gone for a ride and are staying in one place for more than 15 mins, make sure you bring a charger with you.
A 36v SLA Smart Charger (triple charger) works just as well as a single 12v one, and will be able to charge your batteries much faster.
Purchase at least ONE 12v Smart Charger, (There's a REALLY nice one at Walmart for around $30 and is able to charge at 2amp, 4amp and 6amp, and ALSO, has a mode to desulfate batteries {it accomplishes this by throwing 15v+ on the battery if it detects sulfation, which will lossen the sulfates, and then will charge the battery normally, and does this all automatically})

I can make a 36v 18ah battery pack last 800 charges with 100% distance still available on the batts.

If you are only going to use the SLAs for a year, then you can go to 11.85 per battery everytime (34.55v, but mostly the controller limits you to LVC at below 35v, so you should be ok...

IF your controller does NOT have an LVC, then you MUST WATCH your batteries. If you continually go below 35v you will see a dramatic decrease in range, in the range of a weak.

My .02
 
your two cents is worth more actually. In my case the voltage drop is noticeable at about 12.5 per battery and I start looking at getting home. I have the battery tender from walmart but it doesn't say that it has a desulfinator it does however routinely toss 14.25v at the battery during the charging cycle.

I reconfigure my battery packs so often I have broken the taps off the 12ah set I started with almost a year and a half ago. Those had to be tossed. I have a 17ah set that have screw posts and those are going strong at almost a year. I also put mine on the battery tender when I put the bike away and leave them on it till I ride again. I have one for each battery.
 
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deacon said:
your two cents is worth more actually. In my case the voltage drop is noticeable at about 12.5 per battery and I start looking at getting home. I have the battery tender from walmart but it doesn't say that it has a desulfinator it does however routinely toss 14.25v at the battery during the charging cycle.

I reconfigure my battery packs so often I have broken the taps off the 12ah set I started with almost a year and a half ago. Those had to be tossed. I have a 17ah set that have screw posts and those are going strong at almost a year. I also put mine on the battery tender when I put the bike away and leave them on it till I ride again. I have one for each battery.
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The ABSOLUTE key to battery efficiency for the long term is to ALWAYS CHARGE IT IMMEDIATELY AFTER USE..
Once you've noticed the battery(s) has hit 12.5v (37.5v) without a load on it, start pedaling or keep amperage usage below 5a or so until you get to a place where you can charge it immediately.
 
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I recently burned up some nimh batteries which were piggy backed onto a sla pack. I let the pack get too low and had to push the bike. When I pushed it, I let the run down battery pull the bike up the hills. I found the melted battery wrappers when I got home. Another lesson learned.
 
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