diy solar

diy solar

Lipo4 battery storage

S

Sik-wit-it

New Member
Joined
Oct 7, 2023
Messages
60
Location
Virginia
I have two 24 volt LiPo4 batteries 100ah each I also have two 12 volt lipo 4 batteries 400ah each I want to tie the two 12v and series which will be 400ah 24v is there anyway I can tie the two 12 volt batteries in series to the two 24 volt batteries to get a total of 600ah even tho the 24v 100ah are less in ah then the two 12v 400ah that will be in series to make 24v will this work.
Two 24v 100ah in parallel to make 200ah tied to the two 12v 400ah in series that will e total of 400ah together the total will be 600ah ???
 
Last edited:
Yes. 600Ah.

Best option would be to attach each 24V battery to bus bars creating a 3P 24V bank.

VERY important that the two 12V be charged to full individually and preferably again in parallel to ensure they are top balanced.

1712876959826.png

Once established, you should use a clamp DC ammeter to confirm that the batteries are each operating within spec during high current charges and discharges.

See link #6, section 3.3 for best practices in paralleling batteries.
 
sunshine_eggo said:
Yes. 600Ah.

Best option would be to attach each 24V battery to bus bars creating a 3P 24V bank.

VERY important that the two 12V be charged to full individually and preferably again in parallel to ensure they are top balanced.

View attachment 208782

Once established, you should use a clamp DC ammeter to confirm that the batteries are each operating within spec during high current charges and discharges.

See link #6, section 3.3 for best practices in paralleling batteries.
Click to expand...
sunshine_eggo said:
Yes. 600Ah.

Best option would be to attach each 24V battery to bus bars creating a 3P 24V bank.

VERY important that the two 12V be charged to full individually and preferably again in parallel to ensure they are top balanced.

View attachment 208782

Once established, you should use a clamp DC ammeter to confirm that the batteries are each operating within spec during high current charges and discharges.

See link #6, section 3.3 for best practices in paralleling batteries.
Click to expand...
So the 24v 100ah batteries won't drain down first being there are less in ah ?
 
sunshine_eggo said:
Yes. 600Ah.

Best option would be to attach each 24V battery to bus bars creating a 3P 24V bank.

VERY important that the two 12V be charged to full individually and preferably again in parallel to ensure they are top balanced.

View attachment 208782

Once established, you should use a clamp DC ammeter to confirm that the batteries are each operating within spec during high current charges and discharges.

See link #6, section 3.3 for best practices in paralleling batteries.
Click to expand...
sunshine_eggo said:
Yes. 600Ah.

Best option would be to attach each 24V battery to bus bars creating a 3P 24V bank.

VERY important that the two 12V be charged to full individually and preferably again in parallel to ensure they are top balanced.

View attachment 208782

Once established, you should use a clamp DC ammeter to confirm that the batteries are each operating within spec during high current charges and discharges.

See link #6, section 3.3 for best practices in paralleling batteries.
Click to expand...
So the 24v 100ah batteries won't drain down first being there are less in ah
Supervstech said:
Correct, as long as the cables feeding the batteries are same resistance, and the arrangement is balance drain.
Click to expand...
What do you mean by same resistance
 
Supervstech said:
Those appear to be the cheap brass bussbars, very high resistance, and not nearly the amp capability they advertise…
Click to expand...
So send me a picture of the ones you think I need.
And I don't think I'm pulling nowhere near 200ampsfrom the batteries at one time tops maybe 20amps
 
sunshine_eggo said:
Yes. 600Ah.

Best option would be to attach each 24V battery to bus bars creating a 3P 24V bank.

VERY important that the two 12V be charged to full individually and preferably again in parallel to ensure they are top balanced.

View attachment 208782

Once established, you should use a clamp DC ammeter to confirm that the batteries are each operating within spec during high current charges and discharges.

See link #6, section 3.3 for best practices in paralleling batteries.
Click to expand...
Why can't I just tie the batteries together the same way without the busbar?
 
Put the 12 volts in series and go from positive to positive to negative to negative to each battery and then to the bus bar
 
Sik-wit-it said:
Put the 12 volts in series and go from positive to positive to negative to negative to each battery and then to the bus bar
Click to expand...
One more question would the 24 volt 100 amp hours drain before the 400 amp hours and how low can I set the batteries before charging again I usually go down to 22 to 23 volts before charging again with utility or solar
 
Sik-wit-it said:
Put the 12 volts in series and go from positive to positive to negative to negative to each battery and then to the bus bar
Click to expand...
I'm having a problem picturing this, but if you have 8 cells connected in series (4S in series with 4S), when you connect the individual cells in parallel, that will be a dead short (and there will be sparks, fear and then sadness). Hopefully a video too.
 
Last edited:
MisterSandals said:
I'm having a problem picturing this, but if you have 8 cells connected in series (4S in series with 4S), when you connect the individual cells in parallel, that will be a dead short (and there will be sparks, fear and then sadness). Hopefully a video too.
Click to expand...
haha, yeah that is worded in an especially frightening manner.
 
MisterSandals said:
I'm having a problem picturing this, but if you have 8 cells connected in series (4S in series with 4S), when you connect the individual cells in parallel, that will be a dead short (and there will be sparks, fear and then sadness). Hopefully a video too
Click to expand...

MisterSandals said:
I'm having a problem picturing this, but if you have 8 cells connected in series (4S in series with 4S), when you connect the individual cells in parallel, that will be a dead short (and there will be sparks, fear and then sadness). Hopefully a video too.
Click to expand...
 

Attachments

  • Screenshot_20240413-102935_1.png
    Screenshot_20240413-102935_1.png
    106.8 KB · Views: 6
Supervstech said:
Correct, as long as the cables feeding the batteries are same resistance, and the arrangement is balance drain.
Click to expand...
Hello I have one more question before I rearrange my battery so you don't think the 24v 100ah batteries will drain first and shut my inverter off being the other batteries is 400ah I think the 100ah will drain first and shut off unless I set the charge controller not to let the batteries drain that low but then I will be loosing ah from the batteries especially the ones that's 400ah I wouldn't get near close draining them down being they hooked up with the 100ah am I correct?
 
You must log in or register to reply here.

Similar threads

H
AGM Series Parallel Balance
Replies
2
Views
156
haycord
H
C
SOK BMS wildly inaccurate
Replies
3
Views
190
PotusGobbleBottom
PotusGobbleBottom
D
Different Batteries in Parallel Uneven Discharge
Replies
7
Views
538
rhino
rhino
Scoob-SanDiego
LifePo4 batteries in 2S2P vs 2P2S for my 24V inverter setup?
Replies
6
Views
784
Akane
A
C
Charge controller settings?
Replies
15
Views
375
Q-Dog
Q-Dog
Back
Top