Help Me Change capacitors

[monsterkali666]

Hello
I have a 75.6v full,18s battery which is on the last mile,will be dead soon.
Bought a 20s 36A battery.
My controller is a 60v one.

I want to upgrade the caps.

Mosfets seems to be good for 98v
Type Designator: SVG105R5NT
Marking Code: 105R5NT
Type of Transistor: MOSFET
Type of Control Channel: N -Channel
Maximum Power Dissipation (Pd): 200 W
Maximum Drain-Source Voltage |Vds|: 98 V
Maximum Gate-Source Voltage |Vgs|: 20 V
Maximum Gate-Threshold Voltage |Vgs(th)|: 4 V
Maximum Drain Current |Id|: 120 A
Maximum Junction Temperature (Tj): 150 °C
Total Gate Charge (Qg): 80 nC
Rise Time (tr): 40 nS
Drain-Source Capacitance (Cd): 565 pF
Maximum Drain-Source On-State Resistance (Rds): 0.0055 Ohm

Caps are 80v330uf, and 200uf
I want to upgrade to 100v caps, but which ones to choose?any links?

For the 12v part,i have the SD4938 ic

• Input voltage: 20V~150V
• Adjustable output voltage including: 12V, 15V and 18V

so i can leave it as it is.
I attach a google drive folder link, for you to see some pictures of the controller
Thank you.

 

[amberwolf]

I would recommend Rubycon, Panasonic, as good brands, purchased from Mouser, Digikey, Farnell, or a well-known distributor.

I do not recommend anything from non-distributor sources, as you can't know if they are genuine, or rejects, or salvage, or remarked other products, etc. That sort of thing isn't likely all that common, but it is a real risk.

The higher the temperature they are rated for, the longer they will last at the elevated temperatures common inside controllers being pushed beyond their original design limits. Spec sheets for each part can give you the chart for hours of lifespan vs temperature for any specific part.

Pick capacitors as much higher in voltage as you can fit in there, and they will also last longer than ones closer to the voltages your system operates at.

Each capacitor has an ESR; for your usage the lower that number is the better.

More capacitance can help smooth out ripples in voltage from current demands, but there is a limit to what you can use--the higher the capacitance, the larger the inrush current at initial charge, and the larger the capacitors will physically be, etc. If your controller operated correctly at the present total capacitance, then you can probably safely stick with that amount.

 

[monsterkali666]

Thank you @amberwolf for your answer.

I have:
3x 80v 330uf
2x 80v 220uf
1x80v 100uf

What i found so far:
100v 330uf 105 C

Ripple Current:	2.38 A
ESR:	23 mOhms

100v 220uf 105 C

Ripple Current:	1.8 A
ESR:	34 mOhms

100v 100uf 105 C

Ripple Current:	1.5 A
ESR:	84 mOhms

I am also searching for the Rubycon.

Also, i will try to check voltages vs lenght. To do what you suggested :
"Pick capacitors as much higher in voltage as you can fit in there, and they will also last longer than ones closer to the voltages your system operates at."


Also,about ESR (even i didn't fully understood it) those values seems to be the lowest when selecting panasonic, 100v, and the uf.
I will post again when i find another models.

 

[monsterkali666]

I'm back:
Due to high shipping cost, (North America to Europe)i ended up ordering the following,from TME :

EEUFS2A221PANASONIC electrolitic; low ESR; THT; 220uF; 100VDC; Ø12,5x25mm ​

link​

UPW2A331MHDNICHICON electrolitic; low ESR; THT; 330uF; 100VDC; Ø16x25mm​

link


UPW2A151MHD NICHICON electrolitic; low ESR; THT; 150uF; 100VDC; Ø12,5x25mm
link


I hope it's ok.We'll wait and see.