Questions tagged [supercapacitor]
Very high energy-density capacitors, typically measured in farads.
359
questions
0
votes
1
answer
68
views
Cyclic Voltammetry for a Capacitor - Positive Current, Potential is decreasing?
In the boxed red region, why is the potential decreasing when the current is still positive? To my understanding, when the current is still positive (i.e. not changing direction), the capacitor will ...
- 1
1
vote
1
answer
149
views
Supercapacitor discharging fast when there is no discharge path present
This question is a continuation of my previous question, but different from that.
I am using a PCA85073A RTC in my design. On some boards, the supercapacitor discharges very fast (5 V to 1.1 V in half ...
- 2,593
0
votes
1
answer
77
views
What will happen if I2C pull up voltage became zero
This is a continuation of this question.
In my board RTC I2C lines are pulled up to controller supply voltage and the controller supply voltage will be off when the system is off.
At that time also ...
- 2,593
3
votes
2
answers
517
views
Super capacitors derating
I want to use supercaps in a system for minimal power interruption backup (1-2 seconds). My systems works at - 40 to 85°C.
I have seen that supercaps are usually rated for 1000 - 2000 hours at max ...
- 107
16
votes
2
answers
4k
views
Why is my super-capacitor self-discharging so fast?
I'm experimenting with a night light powered by a mini solar panel charging a super-capacitor instead of battery. (I know, I know. It's not recommended for this usage but I want to try it anyway). It ...
- 293
4
votes
1
answer
1k
views
RTC super capacitor is discharging very fast
I am using a PCA85073A RTC in my design. On some boards, the supercapacitor discharges very fast (5V to 1.1V in half an hour.)
This happens when we turn off 5V_uC.
The circuit is given below.
All the ...
- 2,593
0
votes
1
answer
58
views
Wide input voltage capacitor charging control
I'm working on a project in which we are using a bank of inexpensive 100 μF caps (up to 20 of them) to keep a microcontroller powered up long enough to do housekeeping for shutdown when the main power ...
- 85
1
vote
3
answers
118
views
Supercapacitor minimum voltage
I want to use a supercapacitor ( Lithium Ion 3.8V 30F) to be charged only by a small solar panel. And the circuit will only do something between between 2.7 and 3.3 V. In standby mode the circuit will ...
- 11
0
votes
1
answer
102
views
Wire size for 16 V, 83 F capacitor [closed]
I have a capacitor bank circuit (16 V, 83 F). I got it from AliExpress. I am planning to install it in my car parallel to my car battery (car battery capacity: 12 V, 50 Ah). Could you please suggest ...
0
votes
2
answers
136
views
Test circuit for a solar panel used to power a supercapacitor
I was hoping to power a device with a supercapacitor that would provide power when there isn't light available, so essentially I just need the solar cell to charge the supercap as fast as it would ...
- 11
0
votes
0
answers
78
views
Super capacitors and getting same current burst out every time using boost converter?
I need to use a supercapacitor to power a circuit for short pulses evenly. So with the same current out every pulse. To do this, I thought to use a boost converter to get a constant current out every ...
- 1
0
votes
2
answers
73
views
Replacing Li-ion battery in a game controller with a supercapacitor
My game controller's Li-ion pouch battery is swollen and has died. I was thinking if it was possible to replace the internal battery with capacitor/supercapacitor. I don't need the wireless ...
0
votes
1
answer
294
views
How to replace a lithium-ion battery with a super-capacitor in electronic device?
I have a mobile WiFi router, which contains 3.7 V pouch lithium-ion battery. But I use it only in one fixed location where the charger always plug in. The problem is, the Li-ion pouch cell will puff ...
- 101
1
vote
1
answer
119
views
Low power circuit design for powering an e-paper display
This is a follow up to my last question on Low power circuit design for turning an LDO on/off at specific voltage levels, where I wanted to find a low power way to turn an LDO on/off at specific ...
- 77
2
votes
1
answer
207
views
Low power circuit design for turning an LDO on/off at specific voltage levels
I am designing a low power circuit that uses the TPS61023DRLR for energy harvesting, charging a 1.5F ...
- 77
0
votes
1
answer
261
views
Design for passive power backup for ESP32 for a few milliseconds
I am designing a logger system with an ESP32 in which the logs are uploaded to the IoT cloud and parallelly logged to a local SD card. On Power loss detection, I want the ESP32 dump all the data that ...
0
votes
3
answers
175
views
Use supercapacitor to power microcontroller
simulate this circuit – Schematic created using CircuitLab
I try to solar charge a supercapacitor C1. When it's fully charged, I use a Zener diode D2 to the gate of an logic MOSFET M1, which ...
- 101
0
votes
0
answers
50
views
Charging a super cap with a Li-po battery while maintaining charge
I have a 3 V 100 F capacitor and 400 mAh 35 C battery, the battery is to be charging the super capacitor and maintaining charge until a button is pressed to discharge the super cap. I am stuck with ...
- 407
2
votes
1
answer
292
views
Designing boost converter for a supercapacitor source and LED load
I have a 2.7 V 100 F supercap, that would equal 364.50 J of energy based on E = 1/2CV^2. If my load is a series of 4 LEDs with a stack forward voltage of 12 V and forward current of 3 A that would ...
- 407
0
votes
0
answers
155
views
SuperCapacitor Charger with BQ25173
I am asking about supercapacitor charger with BQ25173 IC. I examined the datasheet and designed my circuit for about 13 mA, but when I built the circuit, the current that was needed to charge the ...
1
vote
0
answers
178
views
Super capacitor causing overcurrent protection
I'm making a power-supply circuit for some MCUs using a battery charging-discharging protect module MH-CD42 (both input and output is 5 V).
The module's datasheet says it has a 0.3 seconds switch time ...
- 111
-1
votes
1
answer
70
views
Leakage current in supercapacitors stack
Given a circuit of four hybrid supercapacitors in series, connected in parallel with another branch of supercaps in series (4s, 2p), where the leakage current is illustrated as a parallel resistance ...
- 135
0
votes
3
answers
1k
views
Using capacitor bank in parallel with lead acid battery
I saw some DIY projects about boosting car lead acid batteries. A supercapacitor bank is connected in parallel with a lead acid battery to stabilize the supply.
However, in the market, I can only find ...
- 343
0
votes
0
answers
251
views
How can I simulate a super capacitor in LTspice?
I am trying to simulate a super capacitor in LTspice but it is not giving me the correct discharge time as it should be theoretically.
Has anyone also faced this issue? Please let me know how to ...
3
votes
2
answers
829
views
Supercapacitor to prevent temporary power supply voids
Hello and sorry for the improper title!
We need to transmit about 50 W (5 V 10 A) through a slip-ring-ish to drive some rotating electronics and LEDs.
We are using a 5 V 25 A LED power supply.
We are ...
- 59
2
votes
0
answers
73
views
Is there any supercapacitor that is hermetically sealed?
Does high altitude affect supercapacitors?
At high altitudes mostly hermetically sealed capacitors are used, so is there any supercapacitor that is hermetically sealed?
- 21
0
votes
0
answers
93
views
Super capacitor charging circuit
I am trying to build a circuit to power a system for about 30s-1min after we have a power loss (12V going off), so my microcontroller and radio transmitter can send a message alerting the power loss.
...
0
votes
2
answers
297
views
USB inrush current limiting, charging super capacitor
I am trying to charge a supercap over USB. I understand I need to limit the current (ref: usb.org)
This has been discussed a lot here, for example: here and here, but I believe my requirements are a ...
1
vote
3
answers
356
views
Help with power buffer using capacitors
Looking for some help on how I might be able to add a power buffer of around 1 hour to an IC using super-capacitors, and be able to recharge it within 5~15 minutes after a power disconnect.
Looked ...
- 13
1
vote
1
answer
644
views
How does balancing via resistors work? Why isn't it needed inside of batteries?
I am building a hobby project - a sort of supercapacitor powerbank, where I basically connected twelve 500F 2.7V supercapacitors in series. Despite these capacitors being from same manufacturer and ...
- 487