3 ms·
What is a Lithium-ion capacitor?
- LorenPechtel 4mo agoAnd no mention of the self discharge rate.
- deleted 4mo ago[deleted]
- rpaddock 4mo agoFor a similar part in this class: Low Leakage Current as small as 1µA Low Self-discharge rate, 72 hours @ discharge <5% https://abracon.com/datasheets/AHCR-S04R0S.pdf https://abracon.com/datasheets/AHCR-S04R0S.pdf The more the Farads the higher the leakage. The higher the tempature the higher the leakage.
- LorenPechtel 4mo agoThat would work for most UPS applications, but it looks like the price is still too high.
- deleted 4mo ago[deleted]
- mrDmrTmrJ 4mo agoLet's say you want to make a hybrid car lighter-weight. Where is this useful? Power density and cycle life are truly impressive. Energy density is super low
- traverseda 4mo agoRegen braking,
- ricardobeat 4mo agoInterestingly it seems to have some applications for high peak power and regen, they had a car in the Dakar rally: https://www.jtekt.co.jp/e/products/capacitor/capacitor_mobility.html#id_ex04 https://www.jtekt.co.jp/e/products/capacitor/capacitor_mobil... https://www.jtekt.co.jp/e/engineering-journal/assets/1019/1019e_21.pdf https://www.jtekt.co.jp/e/engineering-journal/assets/1019/10...
- colechristensen 4mo agoYou would use these to provide peak power in a system that had short term power needs that were high above the average power needs AND had that power requirement as a bottleneck. Energy is the bottleneck for cars though, not power. unless you're wanting your prius to accelerate like a ferrari Maybe it would be useful for less losses with regenerative braking? These would presumably be able to charge much faster and then trickle that power out to the normal battery. You'd need actual power numbers for a car to determine if it would be useful or not. In other words this is for "boy I wish I didn't have to have so much extra battery capacity in order to get the power I need" situation which... cars don't have. Maybe in F1?
- marcosdumay 4mo ago> unless you're wanting your prius to accelerate like a ferrari That's the point of a hybrid.
- dcrazy 4mo agoIt’s the best part of any electric drivetrain. Especially when you can remap the throttle to really launch from zero. :) (I find that electric acceleration makes highway merging much safer.)
- LoganDark 4mo agoMy EV has the opposite problem, something like half throw is full throttle and then the rest of the pedal does nothing. They do it for marketing reasons but I still don't like it
- marcosdumay 4mo agoMy ICE car does the same. The only use for almost half of the pedal travel is shutting down the speed limiter when it's active, with no change at all when the limiter is off.
- dcrazy 4mo ago
- rpaddock 4mo agoFor anyone that wants to see a real data sheet: Nominal Voltage: 4.0V High Power and Energy Densities Cycle Life > 50K Cycles Capacitance Range: 10F-1200Farads https://abracon.com/product-lineup/frequency-control-timing-devices/atomic-clocks/rubidium-oscillators/lic-lithium-ion-hybrid-supercapacitors https://abracon.com/product-lineup/frequency-control-timing-... Note that the original data sheets said that these could be wave soldered. ABSOLETLY NOT. Even hand soldering they must be treated with respect, a lot of respect. One of the major problems with these is there a minimal voltage that they must not go below. Their life gets shortened. I've never seen data on how much. To my knowledge Li-Ion Capacitors were first introduced to the market by Taiyo-Yuden in 2010. They are no longer in this market. I wrote a blog about it back then: http://blog.softwaresafety.net/2010/11/introducing-lithium-ion-capacitor-and.html http://blog.softwaresafety.net/2010/11/introducing-lithium-i...
- rpaddock 4mo agoThe direct link to the data sheet: https://abracon.com/datasheets/AHCR-S04R0S.pdf https://abracon.com/datasheets/AHCR-S04R0S.pdf
- pseudohadamard 4mo agoSo it's some of the performance of a supercap (hundreds of thousands of cycles, up to million-hour lifetimes with a bit of care, less finicky about soldering) with all of the safety of a LiIon battery? I think I'll give it a miss, although it probably has niche applications like use-once military systems where you're not worried about long-term performance before it disassembles itself.
- supertroop 4mo agoDumb question but I though capacitors store energy and not power?
- azornathogron 4mo agoThey store energy but there's a limit to how quickly you can get that energy out, hence a limit to power. And I suppose you can kinda talk about them "storing power" in the sense that power is what you might be interested in getting out of them. At least, that's my understanding of it.
- martinbfine 4mo ago[dead]
- aftbit 4mo agoPower is just the time derivative of energy, like velocity is the time derivative of position. Both batteries and capacitors store energy, which they can release at some given peak and average power. Batteries tend to focus more on energy density (energy stored per weight), while capacitors tend to focus more on power density (rate of energy stored or released per weight).
- mikepurvis 4mo agoI think that just reflects that the typical usage for a capacitor is smoothing out some very spiky load that runs at a high frequency, say a microcontroller running at 100MHz. The average power needs of the MCU are low, but it's drawing almost all of it in a big burst on every clock tick (10ns). Power supplies handle that badly, and the pulses turn your supply traces in a big antenna and suddenly you're an unlicensed FM radio station. So for the capacitor that's put in place to buffer that load, the total capacity is important, but what really matters is that the part can manage that 100MHz charge/discharge cycle.
- supertroop 4mo agoYou could have just said yes.
- SoftTalker 4mo agoLarge, charged capacitors are pretty frightening. Batteries too, but their discharge rate is limited to the speed of the chemical reaction.
- LoganDark 4mo agoAre capacitors not limited by a chemical reaction?
- SoftTalker 4mo agoNot AFAIK. A simple capacitor is two metal plates separated by an insulator, allowing an electrical charge to accumulate. Discharge would only be limited by the current-carrying capacity of the wiring.
- deleted 4mo ago[deleted]
- modeless 4mo agoNot generally, no. Capacitors usually store electrons in a conductor so they are free to move instantly. Movement of free electrons within a conductor is not considered a chemical reaction.
- mikepurvis 4mo agoaka a lightning bolt
- groos 4mo agoNot really as large capacity capacitors (this one seems to be 4V) tend to be low voltage as well. You can touch the terminals without harm but attempting to short them is going to be, er, entertaining. I have accidentally touched a 200V capacitor and it was not fun.
- SoftTalker 4mo ago