are my cell soldering drawings ok building a battery expandable

Hi everyone,
Are you available check at the drawings i did? I have a need for knowledge to know where to do the soldering in order that i can use
a bms with 4p 13 battery that has the possibility to get a second 4p 13s battery to it for longer rides(8p13s total when combined).
If i succed in this battery, it would give me a sens of autonomy and more liberty on my bike.
-I already have 110 vtc4 sony cells,
-one feet square copper thin plate
-i intend to use xt60 connector

it is my first assembly, feel free to open to copypaste the picture in paint to modify the drawing.
the color of bronze gold is to represent copper slice


note that i will be buying a xiondga 2 speed motor with its controller
here are the attached same pict
https://www.cjoint.com/c/HHsfDCwhiU3
https://www.cjoint.com/c/HHsfFoT8DI3
https://www.cjoint.com/c/HHsfFZ8gP43

I do not like it. Two stings of 13S4P with only one BMS. You will be connecting each group using connectors.

What happens if you run the first string down to 42V and the second string is at 47V? It will be awkward to get them equalized for charging, We will ignore the complexity of 13 cross connects with heavy wires. Also will ignore the drawbacks of a soldered battery.

Build two 13S4P with a BMS on each.It's much more flexible.

its a recipy for disaster.

NEVER put the parralel wires in like that. if you got 2 batteries you need 2 bms's. at the end you only need to hook up the terminals togeter with a Y splitter capable of taking the current.
i would recommend getting a heavy duty diode on each of the Y termals legs in order to prevent any backfeeding between the batteries. that way you wont set your bike on fire when you connect a charged battery next to a empty one. because that will happen sooner or later.

or just do it the right way and make one big battery. that way you will massivly increase the lifespan of the cells and makes you enjoy having a huge range all the time. it is a cheaper, more efficent, better and just makes more sense.

Solder out. There are many threads of making a spot welder out of a microwave and or kits like the K weld kit but you need to assemble it yes a little costly. Copper gets really weird on a battery turns all green and s*** best to use Nickel Plate something or other

hi
tx for the suggestions
if it can conduct electricity i will keep copper cause i already have bought it.. apart from being green any other cons?

for the soldering, it seems since i only will build 2 batt, building a tool seems another time investment.... it is already long to build battery already... how long does it take to build a tap welder approx and cost aprox?

Hi,

if i use 2 bms. can i still use the 2 batteries together like in this drawing with 2 Y connecting them to the motor and charger?

can someone check if the soldering places (black) dot and Bminus Pminus and Cminus are also connected at the right place? any improvement possible?

hi,

could you review my last drawing with a the Y connection?

I also would need advice on the type and gauge wire i should use. at leats 60 tp100amps maybe?
i think i will use xt60 connector since they are cheap and can handle from 60 to 150 amps according to reviews.

Also my last post felt between the images it was
if i use 2 bms. can i still use the 2 batteries together like in this drawing with 2 Y connecting them to the motor and charger?

can someone check if the soldering places (black) dot and Bminus Pminus and Cminus are also connected at the right place? any improvement possible?

you can do it like this but it is still very not recommended. please reconsider amd just make one big pack. it will give you superior performance in every way and increases lifespan greatly.

HI

the risks of being steal are high and i dont want to carry a large battery around. I dont care much about life spaw since i wont use it a lot.

as long as the cell stay equal it is fine with me.

So apart from making just one battery is there a better way to build a separable battery than my 2 bms drawing? are the soldering point a the good place? Are the y connection in an ok setup?

if you could give exemples of what wrong could happen, it would bring clarity to why you say it is very not recommended.

thx