Dual 48 volt battery setup

[R4yD8R]

Greetings, I am in the process of setting up a dual 48 volt battery system on my DIY E-bike. I installed a conversion kit on a mtb I have about a year and a half ago and it's been decent for the most part but some of my commutes push the battery to it's limits and if I forget to put my battery on charge right away I don't make it home and either have to pedal which sucks worse than it did before I had the motor or jump on public transportation and on the way home is the worst time to have a dead battery. I just want to be home.

I already ordered 2 new batteries which are exactly the same as the one that came with the kit. They are 48 volt 13aH Hailong style. I was originally planning to get ones with more capacity such as 15 to 20 aH but they are significantly more costly and I found a deal that just could not n be passed up on the ones I got. They are regularly priced at $249 each. I saw a coupon for $30 thinking it would be only for the second one but when I checked out both batteries were $30. I couldn't believe it, my cart subtotal went from over $500 to $152 and change as I also had a couple of other things with the batteries.

Which brings me to the reason I am posting. I won't have the batteries until sometime between May 1 to May 7th so in the meantime I've been doing more research into the wiring. I have a decent grasp on most of it and I'm capable of doing the actual work involved because none of the batteries nor the controller have the common connections that the adapter has on it so I'll be doing some custom wiring work, which I more than likely would have anyway because I want to keep things neat and as tight to the bike as possible.

My confusion still lies with the balancing/equalizing of the batteries. The new ones are coming from the same supplier at the same time however I know that's no indication that they will be matched voltage wise. The adapter I bought is more than just a wire jumper, it has a device of some kind wired into the line between the 2 inputs and the output and it's called a dual battery pack discharge adapter however from what I can gather it sounds like I still might need another device to actually do the balancing!/equalizing. If anyone has any input on this, it would be greatly appreciated.

Dual Battery Pack Switch Balancer, 20V-72V Double Battery Discharge Converter Providing Lasting Power for Electric Bike https://a.co/d/fRoplEY

This is the device o bought a along with 3 of these...

DROK 48v Battery Meter, 10-100v Marine RV Battery Capacity Volt Monitor 12v 24v, Lithium Battery Voltage Fahrenheit Temp Indicator Gauge https://a.co/d/1EdhEbP

This is what I'm curious to know if I need as well?

LiTime 48V Battery Equalizer, Active Balancer for 24V/36V/48V Battery Bank, Supports for LiFePO4 Lithium Battery, Lead Acid, Gel, FLA, SLA Battery, Perfect for RV, Solar, Trolling Motor, Off Grid https://a.co/d/6rWWFS9

 

[Chuy]

It would be useful to see a pic of what you have. I don't have direct experience with dual batteries. From what I have come across on utube, they have only ever mentioned the first device posted. It draws current from both batteries, continuously drawing current from the battery with the higher voltage. Thats why it doesn't matter if one battery has a higher capacity, but the rated voltage for both batteries has to be the same.

 

[fabbrisd]

1. Battery Blender : this allows both batteries to discharge safely in Parallel to power your bike. Parallel blending means both batteries discharge to/at same level. Please note for Charging - you need to charge each battery seprately - a Blender wortks Downstream (discharge) and does not Upstream (charging).

2. If you have correct Display set for 48V - it will show % battery based on 48V - since your blending - both batteries even - you do not need to add unecessary meters. Since the Display measure V post-controller - reading V at the battery itself is technically more accurate but difficult to correctly attached meter at the battery s

 

[fabbrisd]

3. "Balancing Cells" in a "individual battery" is best left to be discussed with other experienced swimmers togther at the deep end of the pool. You are currently at the shallow end with your 1st eBike.
DO NOT ADD THAT BALANCER which is NOT designed for this type Lithium Ion battery. Lithium Phosphate is NOT our battery che
DO NOT buy/add a Fast Charger - charge each battery with a charger rated a Amp match by the battery supplier.
It is rarely possible to charge each battery to the exact same level (avoid charging to 100% - best to charge to 80%)
but that is what a Blender is for - it will discharge the Higherbattery until it matches the Lower then safely discharge from
both.