I need advice to choose the best AGM deep cycle batteries.

[neptronix]

Could you measure it and see if a 24v battery would fit in one part of the shape and bricks in another?

Lifepo4 is 3-4x denser per kw-hr so it's likely a 24v will fit in a half compartment.

A visual would be helpful, if you can get it.

 

[ZeroEm]

Batteries come in different sizes, get a measurement of your box and match a pair of batteries. You don't need one big battery you can get two 12V.

 

[ZeroEm]

YellowBuzzaroundEX we are trying to help you. everyone here knows lead batteries are not a good value. It's like light bulbs we all use led now right.

 

[neptronix]

Batteries come in different sizes, get a measurement of your box and match a pair of batteries. You don't need one big battery you can get two 12V.

but that complicates charging which isn't acceptable here

 

[Papa]

Yes, but how are you charging them?

My post (#22) was intended to address your misconception about "balancing" series connected LiFePO4 12Vdc batteries.

What source (120Vac grid or 48Vdc solar) is used to charge the batteries is irrelevant. You charge with ONE battery charger - I do likewise with ONE battery charger. You charge at 24Vdc (2x12Vdc series connected batteries), I charge at 48Vdc. (4x12Vdc series connected batteries).

Edit to add: All voltages referenced are nominal.

 

[neptronix]

In this case do you have batteries designed particularly for that?

Some people have problems with using batteries in series, it involves a diode, otherwise some BMSes can go pop, but this more refers to ebike batteries ( i'm unfortunately thinking in this frame of mind too )

I like simple systems though so if we can use a single 24v and a brick or two, that's a workable solution

 

[Papa]

In this case do you have batteries designed particularly for that?

Do you mean 'designed' for series connections of 12Vdc lithium?

Yes. As per Litime's owner's manual.
All I did was remove the four aging lead acid batteries, and installed the lithiums. The Victron charger i'm using automatically disables the "Equalize" feature because it's not used for lithium.

 

[YellowBuzzaroundEX]

My post (#22) was intended to address your misconception about "balancing" series connected LiFePO4 12Vdc batteries.

What source (120Vac grid or 48Vdc solar) is used to charge the batteries is irrelevant. You charge with ONE battery charger - I do likewise with ONE battery charger. You charge at 24Vdc (2x12Vdc series connected batteries), I charge at 48Vdc. (4x12Vdc series connected batteries).

I think many chargers are used to charge 12V batteries that are connected in series is relevant. One 12V charger per battery or one higher voltage charger for entire system could make a difference in regard to individual batteries staying balanced.

 

[neptronix]

This ain't SLA, in this configuration the BMSes inside the batteries will ensure they are balanced. If for some reason they become slightly imbalanced, leaving them on the charger a bit longer would fix it.

I like a single 24v battery route because there are less parts in the system and therefore less to theoretically break, maybe also slightly less cost

 

[YellowBuzzaroundEX]

This ain't SLA, in this configuration the BMSes inside the batteries will ensure they are balanced. If for some reason they become slightly imbalanced, leaving them on the charger a bit longer would fix it.

I like a single 24v battery route because there are less parts in the system and therefore less to theoretically break, maybe also slightly less cost

If I were to go to LiFePo4 batteries... Then I would prefer one large 24V battery, but that wouldn't fit the physical layout of my battery box. My battery box requires two smaller batteries.

I don't want two LiFePo4 12V batteries connected in series, but I could connect two small 24V batteries in parallel. All I'd have to do is make a new wiring harness for the two batteries that connects them in parallel. That would fit the battery box and I could use one 24V charger plugged into the scooter's tiller.

I would love to buy these French Solise 24V 15AH LiFePo4 batteries, but I don't think they're available in USA.

I could buy these Canbat 24V 12AH LiFePo4 batteries.

 

[Papa]

This ain't SLA, in this configuration the BMSes inside the batteries will ensure they are balanced.

I think many chargers are used to charge 12V batteries that are connected in series is relevant. One 12V charger per battery or one higher voltage charger for entire system could make a difference in regard to individual batteries staying balanced.

Reads to me you are trying to convince me/us that Litime's published recommendation(s) are in error?

I'm sooo done here.

 

[neptronix]

If I were to go to LiFePo4 batteries... Then I would prefer one large 24V battery, but that wouldn't fit the physical layout of my battery box. My battery box requires two smaller batteries.

Measure first and pics would be helpful.

I don't want two LiFePo4 12V batteries connected in series, but I could connect two small 24V batteries in parallel.

That might be more problems to do it in parallel unless you're willing to unify the internal balance leads also.
Remember, this is a much better battery, but it ain't SLA.

 

[Zambam]

As requested by others already, post some photos and model # of your mobility scooter. I built a LiFePo4 battery to replace the sealed lead acid battery in my moped and it's been night and day. No more deep voltage sag, twice the range, much quicker acceleration and higher top speed.

Once you try LiFePo4, you'll never go back to lead. The weight ballast issue seems to be your only hangup. That should not be tough to solve.

 

[ZeroEm]

You don't need chargers connected in series. These batteries are build to connect in series and or parallel. The look like lead batteries and made to fix in their spaces. I'm sure you can get a 24V that will fit the space. refer back to my post.

 

[marty]

That might be more problems to do it in parallel unless you're willing to unify the internal balance leads also.
Remember, this is a much better battery, but it ain't SLA.

Please explain further. I have asked the same question over here.

Merits Pioneer 4 - Battery Recommendation

Scooter Girl has this Merits Pioneer 4 Scooter no go. Diagnose problem to be dead batteries. There are two of these BW1235DC-NB BW1235DC-NB Specifications Took the 2 batteries to battery store. Battery guy tested them with a load tester that looks like this. One battery was bad. Bad as in...

endless-sphere.com

It's going to be snowing here soon and I want to get the big scooter going.