The Cycle Satiator, universal charger for the enthusiasts

[Busybee]

I offer free advice to Sun Tourists with touring e-bikes/trikes with bigger batteries than needed when not touring. When touring away from the plug, solar panels are used, and the solar charge controller goes for full charge, but at home getting occasional use, the thought of keeping the packs fully charged at almost all times by the panels and then used maybe 10% - 20% of capacity daily is painful, and smacks of battery abuse. I'm thinking to offer the following advise. I could be wrong, often am, would rather be right, so I'd like to invite my brethren to vet my advice:

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Heat reduces lithium-ion battery life, and the higher the charge, the worse the effect of heat (above refrigerator temperature). So to minimize battery longevity, use it on an e-bike, keep it outdoors when the temperature is above room temperature (room temp is not dramatically bad, but being in sun on a hot day is), and keep it fully charged whether it's being used or not. It is best not to fully charge a battery, but to store only what is expected to be needed the next day. For maximum longevity in storage, charge to 50% rated capacity, so always recharge to 50% after use, then add more if and when needed.

Think of a bell curve with full charge on one end and full discharge on the other. Best to avoid both. The middle of the bell curve is the hump, so 50% plus or minus 10% is excellent, 50% plus or minus 20% is good, and 50% plus or minus 30% is not so bad, but plus or minus 40% is pushing bad, and plus or minus 50% (full charge and discharge) is maximally bad. So for 'not so bad', charge to 80% capacity, and discharge to 20% of really dead or to when the BMS (battery management system) cuts off power. There is good evidence that charging to 80% (or even less) makes for a happy battery, but the belief that you should discharge to no more than 20% rated capacity is not actually evidence-based. So if your battery is rated for 54.6V full charge, and about 40V discharged, the BMS is allowing maximum charging but disallowing serious discharging to 33V - 35V, so discharging to 40V is not abusive. Charging to 80%, 52.0V, would not be so bad as going to 54.6V when the range is not needed. Being nice to your Li friends means your $1299 battery will last longer.

If you try to harm your battery by discharging it, the BMS should protect it. So a nominal 48V battery (at about 50% charge) can be charged to 54.6V (4.2V/cell or a bit higher) and discharged to about 39V (3.0V/cell) before the BMS cuts off power. Battery manufactures sell capacity, and optimize for capacity (advertised range) at the expense (yours) of battery longevity. If you don't need the maximum range on a given day, put only as many Ah into the battery as needed. If you have a 20Ah battery and need less than 10Ah to do a daily commute, then charge to 50% instead of 100%.

If on Saturday you plan to ride until 50% discharged then turn around and head home, or are touring, then charge to 100%. You need to occasionally fully charge a battery and discharge it to allow the BMS to balance the individual cells in the pack. This needs to be done about every 50 charge/discharge cycles or about every month or two. Fully charging the battery should only be done when full battery capacity is likely to be used or when the pack needs to be balanced. To fully charge after use, if only half the capacity is likely to be needed the next day, is battery abuse.

The problem is that cheap battery chargers that most systems come with won't allow you to select the maximum voltage the battery is charged to. Because battery manufacturers specify a maximum voltage the battery can reasonably be charged to, even though it shortens battery life, makers of chargers use that voltage, and if you don't like it you can stick it in your pipe and smoke your battery for all they care. What is needed is a charger so smart that it does what you tell it to do. Fortunately there is one: The Cycle Satiator http://www.ebikes.ca/shop/ebike-parts/chargers/cycle-satiator.html from Grin Technologies. And, no, I don't get a commission if you buy one, so don't bother telling them I sent you.

 

[robbie]

robbie,

"This is likely the BMS 'tripping' as some of the per-cell voltages are over the specified amount."

Why didn't I see the problem with the original software? The LEDs usually all light within a minute.

We've changed the handling PFC faults from the past, the control board now sense when the power board has entered a fault state, where it would not before. 0.914 had the fault detection be quite stringent, 0.916 has relaxed the bounds a bit.

"Do you know what the actual per cell voltage upper limit on the BMS is?

Charging for several years at 45 volts, 10 amps, with paralleled Ping chargers, if I let it sit on the charger, cycling on and off for 15 minutes at the end, the unplugged battery would sit at 44.4 volts, so 3.7 volts per cell.

But do you actually know at what cell voltage the BMS would cut off charging current? I'd imagine this is probably 3.8V/cell or so. It would also be useful to know at what cell voltage the LED lights on the ping BMS turn on. I'm basically trying to determine if the BMS is cycling on/off, and at what voltage is it doing this, per cell, not pack voltage. Then I can work on re-creating this in our lab here.

"Would you be willing to repeat your testing at 44.0V and see if the charger will enter this voltage fluctuation?"

It would probably double my charge time.

That would be surprising if it did, there's little to no extra capacity gained from charging LiFe from 3.6 to 3.75V. If the balancing function still works at 3.6V/cell then theres no point in charging to 3.75V/cell, and if 3.6V/cell doesn't cause the PFC to trip from BMS cycling, it would get you charging and balancing again.

 

[Warren]

robbie,

Human memory is not to be trusted. I just went back to my old emails. From 06/26-06/29

"On the first charge, I used the "36" volt LiFePo4 default setup. It finished charging at 40.5 volts, not high enough to start the BMS balancing. I then setup a lithium profile with 44.4 volt bulk rate, and it did cycle the LEDs slowly. I don't know what voltage it would have finished at. Being impatient, I then set it up to 45 volts, like my old Ping chargers. This kicked the LEDs on quickly, as per my previous chargers. For the third charge, I set up a 45.0 volt bulk charge. The problem arises, if the cells aren't in perfect balance, which is often the case. If all of the LEDs don't light within seconds of each other, the charger is saying charge complete. It seems happy with the pack sitting at 42.0 volts."

"I used the lithium, 45.0 volt bulk rate setup. The unit does "click" on startup. All but one LED lite within seconds this time, and the charge amperage did taper the last minute. I also saw "connect battery" twice for an instant at end of charge. It read "charge complete", then "connect battery", then "charging", then "charge complete". The charge ended, and the display showed 42+ volts, and 0.1 amp. The voltage kept dropping for the last half hour. It now reads 41.8 volts, and 0.0 amps. The charger never restarted, and all The LEDs are off."

"I did a short ride this afternoon and have now done 7 charges with the Satiator.....I finally got the charger settings sorted out. A lithium profile set to 44.8 volts is just enough to get the LEDs to trigger, and keep the CA reading 44.7 volts, just like the Ping charger. The amp reading will drop to .2 amps, and jump between .1 amps and .2 amps forever. The Signal Lab BMS apparently draws over .15 amps at idle. So the last time I set Complete A to .25 amps."

So, I will try going back to 44.8 volts bulk, and see if the problem goes away.

 

[zlagger]

Hmm...

Would this charger work with the Adaptto system? It uses a Coil and the positive line runs through a phase lead of the controller to control charge. So you can use a 36V or 48V supply to charge an 80V battery pack.

Just thinking out loud here.

If so, what profile would be most appropriate?

 

[Warren]

Grintech guys,

I just recharged the pack with the settings that my email search reminded me worked best with the original software. I have the Full Volts set to 44.8V, the Bulk Amps set to 8.0A, and the Complete A set to 0.40A.

It works almost perfectly. I say "almost" because it takes long minutes, once all LEDs light, for the charge current to taper off from about 4.5amps to the highest Complete A setting the software allows...0.40A. I meant to ask if this could be changed all those months ago, but life got in the way, and I forgot.

I usually watch the end of charge, and stop it manually when all the LEDs light. Pulling the plug then, all LEDs are off in under a minute, and the pack sits at 40.0-41.0 volts. But it would be very useful to be able to set the Complete A much higher. As others here have pointed out, letting the charge taper to a fraction of an amp means the cells end up at 3.7 volts per cell. Not good to do unless you need every last amp hour.

I know I could set the Full Volts lower, but then the BMS doesn't function.

 

[danPedals]

>But it would be very useful to be able to set the Complete A much higher
Warren, you'll be happy to know that the next firmware release should have essentially unbounded termination current, so that your situation can be avoided.

Busybee, I would take care advising ebike neophytes to run batteries until the BMS cuts out, without first cautioning to make sure the battery has a BMS that cuts out on low V. Thank you for the future advice to Sun Tourists.

>Being nice to your Li friends
Excellent! When next I hand someone a pack, I'll have to accompany it with "Say hello to my Lithium friends!"

 

[cal3thousand]

I'm on v.916 and for some reason it will only allow me to select the charge profile current set as 'default', even though I have several that are setup as 'active'.

This started after I updated the firmware, downloaded my profiles, created a new profile, saved my profiles to disk, then uploaded (successfully) the profiles to the Satiator.

Rebooting it manually did not help. Now, the only way to choose another profile is to set the desired one to default and plug in. Should I reflash the firmware?

 

[amberwolf]

Warren, you'll be happy to know that the next firmware release should have essentially unbounded termination current, so that your situation can be avoided.

Where does that info come from?

Excellent! When next I hand someone a pack, I'll have to accompany it with "Say hello to my Lithium friends!"

That has some connotations you might want to consider, first.

 

[Busybee]

Busybee, I would take care advising ebike neophytes to run batteries until the BMS cuts out, without first cautioning to make sure the battery has a BMS that cuts out on low V. Thank you for the future advice to Sun Tourists.

Thanks for the reply, I only have a couple of AllCells and a Falco battery so very limited BMS experience and have never discharged either until the BMS cuts out. Will do so, but I'm thinking 3.0V per cell should be considered 0 SOC and assuming that a good BMS would cut it off about there. AllCell says 40V to 54.8V SOC but I don't know what actual BMS cut offs are in various batts. My info is that 2.5V is seriously discharged and nominal 0 SOC should be about 3.0V. Correct if need be. I'd like to know what the range of BMS cut offs might be in the real world and what a properly engineered one would cut off at.

I mentioned to Rakesh of Falco yesterday that he should carry the Satiator. I'm currently testing his motor. I think he is trying to make a premium system and so should carry a premium charger, but currently having firmware issues, so not quite there yet, so not ready to give a review/recomend yet either. For sun touring the Americas, especially Central and South, I'm advising use of "mission critical" technology. Falco seems the best hope in DDs, but if anyone has other tech that should be considered, please mention. Bionx is a closed system so I'd rather not drink the Bionx coolaid. The needed systems for touring will have a DD for regen braking and pedelec cruising efficiently, and likely a geared hub motor for hill climbing. For those using a trike and pulling a two wheel trailer, with solar panels on each, and a load, two geared eZee hubs in a pusher trailer might not be too many given that duplication can be a good thing in the middle of tech nowhere. On some slopes, two would actually be needed for both power and off pavement traction.

 

[cal3thousand]

I'm on v.916 and for some reason it will only allow me to select the charge profile current set as 'default', even though I have several that are setup as 'active'.

This started after I updated the firmware, downloaded my profiles, created a new profile, saved my profiles to disk, then uploaded (successfully) the profiles to the Satiator.

Rebooting it manually did not help. Now, the only way to choose another profile is to set the desired one to default and plug in. Should I reflash the firmware?

I reflashed the v.916 firmware and I am still having the same issue. I'm currently 'stuck' with 1 profile.

 

[justin_le]

I reflashed the v.916 firmware and I am still having the same issue. I'm currently 'stuck' with 1 profile.

This is very curious. Can you try reflashing the firmware but in the advanced options tab select "overwrite profile data" ? That will do a clean install of the firmware including overwriting the profile section of memory with all the normal default profiles.


See what the behavior with multiple active profiles is then. I'm presuming that when you earlier had a default profile enabled, after turning it on you were pressing and holding the top button to escape the default profile in order to browse the other active profiles? What exactly did you see when you tried to escape the default.

When you have a default, it will always turn on with the default preselected, so you have to do a long button press of the top button in order to get back to viewing and selecting the other active-but-not-default profiles.

-Justin

 

[justin_le]

Warren, you'll be happy to know that the next firmware release should have essentially unbounded termination current, so that your situation can be avoided.

Where does that info come from?

Sorry about that. danPedals is one of the main embedded firmware programmers on the Satiator and piped in because we had just been discussing this change at our last development meeting and I wasn't in a position to post on ES for the past few days when this came up in the thread. He knows now that first ES post should always be an introduction of who you are :wink:

 

[Warren]

Justin,

"the next firmware release should have essentially unbounded termination current...we had just been discussing this change at our last development meeting"

Great! Make it so.

 

[Green Machine]

I am currently testing the Cycle Satiator with different battery packs i have laying around, and some of these battery packs have been laying around for a long time so i am a bit nervous about charging them.

I have the Satiator so i am confident i will be able to easily judge the capacity of my batteries by discharging them and then charging them with the satiator. This is in my view the most exciting feature the satiator offers. I will be able to get a great idea of how much charge my ebike packs are sucking in.

Since i am using mostly cheap home built packs i dont care that much about extending their life as i do to make sure i am safely charging them.

One option which would be really cool in the satiator is a discharge function...this would be amazing for occasionally judging the health of large battery packs which i may not be in the mood to ride until depleted.

My $100 hyperion charger offers this discharge function but not the satiaotor.

One other thing the hyperion offers that the satiator doesn't is a option for a thermometer and a temperature cut off. When i am charging a questionable battery such as a home made hobby king pack, i would feel better if i had a temperature cut off in case things start to go awry.

I'm kind of surprised the satiator lacks a temperature cut off...maybe it does and i just missed it? Or maybe its coming in a later firmware update?

 

[justin_le]

My $100 hyperion charger offers this discharge function but not the satiaotor.

Hi Eric, that's because the Hyperion and other RC chargers are powered from a low voltage DC battery pack rather than from the AC walls. Not only is it easier and cheaper to build that way (single inductor non-isolated DC-DC buck/boost converter), it is super easy to have bidirectional energy flow back and forth into a DC bus. Just like regen on an ebike motor controller, no extra parts are needed, it's intrinsic in the power topology.

With AC, if you want to want to discharge the battery and dump the energy back into the grid with the 0.99 power factor etc. things get a lot more complicated. The Satiator then becomes something of a grid-tied DC-AC power inverter, which is a very different beast (for regulatory certification as well). Most of the power electronic components could in principle be re-purposed for reverse energy flow, and trust that I've got a massive desire to find some way of including that functionality in a later model. The potential uses then could be amazing, not just to drain the battery but also let you use your onboard charger to boost your battery back into AC for running electronics and such. You can imagine how rad that would be on ebike road trips.

The other way to run the discharge would be just to bleed it through an active transistor load and turn it into heat. But since the Satiator is sealed, compact, and fan free, at most it can dissipate about 20-25 watts. That'd be a 20 hour discharge on most ebike packs, not all that useful.

One other thing the hyperion offers that the satiator doesn't is a option for a thermometer and a temperature cut off. When i am charging a questionable battery such as a home made hobby king pack, i would feel better if i had a temperature cut off in case things start to go awry.

Ah that is there. If you connect a 10K NTC thermistor to your battery and wire that between pins 2 and 3 of the XLR port, then it will detect a thermistor present and (at least in earlier firmwares) display the pack temperature on the top scroll screen. We took that off at one point when some users had XLR plugs with shorts on the 3rd pin for charge interlocks and were seeing a "thermistor error" message on the screen, but the plan is to re-enable it across all chemistries and simply not display anything if it is out of range (shorted or open circuit). There isn't any option currently to control the charge based on temperature in the lithium profiles like there is with Nickel, but that will likely be added.

In the long run all pack temperature decisions belong in the BMS circuitry which can be much more temperature and cell aware. So it's not that relevant or important to have on a charger. And hopefully at some point there will be an available supply of easily programmable BMS circuits that you can tack on to your questionably hobbyking batteries to give them at least a faint air of legitimacy.

 

[Green Machine]

Hi justin thanks for listening.

I understand now why discharge function is not offered.

I will try out the temp sensor function....its awesome you have it. I think a lot of ES builders do not use bms and are relying on smart chargers and cycle analyst to take the danger out.....its good if the satiator can be as smart as possible plus easy to use. IT would be cool if the thermometer was a simple plug and play option.....so that i do not need to rewire the pack etc to get it to work...i think it is such an important function it should be super easy to use or no one will use it.

IF you just had a separate thermometer port and a separate add on thermometer that you plug in one end and sticky the other end to the battery pack i think that would be awesome!!! Having a back up to the battery bms wouldnt be a bad idea....and a lot of people are trying to save money or running high power packs and are operating without bms....so easy to use temparature shut off would be awesome function.

I bet here on ES less than 50 percent of users are using a bms.

 

[justin_le]

I bet here on ES less than 50 percent of users are using a bms.

It'll be a major life mission to gradually correct that glaring deficiency!

In the meantime though, it's quite easy to make the temperature sensing completely plug and play with your battery packs. Just use a 3-pin XLR charging plug for your battery packs, and between pins 2 (gnd) and 3 (signal) you wire up a 10K NTC thermistor which is tucked in and among the cells. That does mean you need a thermistor for each of your batteries, but they are really cheap ,like $1-$2 each, so you might as well do that so that every battery once you plug it in will show the pack temperature too. If you want a couple temperature sensing points, then you can use two 20K thermistors attached to opposite ends of the packs but wired in parallel to look like a single 10K thermistor.

In general though it's pretty rare that modern lithium batteries are much more than warm to the touch even after an intense discharge. Is the idea to prevent charging when the pack is too hot, or more to terminate charging in the event of some thermal event taking place? I'm guessing the latter.

I was thinking that a more meaningful use for us to implement would be to have a temperate dependant max charge voltage. This is generally desired with lead acid batteries, where at higher temps you need a lower float voltage or you risk boiling away the electrolyte. With lithiums is is quite the opposite, at very low temperatures (sub freezing) you need to reduce your full charge voltage, otherwise if you charge a cell up to 4.2V when it's icy it will rise to well above 4.2V when it warms up to normal temperatures again.

 

[neptronix]

I like my hyperion a lot, due to it's higher wattage. The only problem is that 14S models are no longer available. And it is in no way portable. When it decides to kick the bucket, i'm screwed. Efficiency of the server PSU & hyperion setup is an atrocious upper 70%, too.

For portability, you could mod a meanwell, but it has kind of a sketchy appearance.

I like this cute OEM looking unit for that reason.

 

[Ykick]

'haven't read every post so pardon my laziness but is there any news about 72V/5A version mentioned on page #1?

Honestly, I only need 67.2V max and 'can probably series 12VDC PS into home charging scheme. But 67.2V would make life on the road so much easier.

 

[cal3thousand]

I reflashed the v.916 firmware and I am still having the same issue. I'm currently 'stuck' with 1 profile.

This is very curious. Can you try reflashing the firmware but in the advanced options tab select "overwrite profile data" ? That will do a clean install of the firmware including overwriting the profile section of memory with all the normal default profiles.


See what the behavior with multiple active profiles is then. I'm presuming that when you earlier had a default profile enabled, after turning it on you were pressing and holding the top button to escape the default profile in order to browse the other active profiles? What exactly did you see when you tried to escape the default.

When you have a default, it will always turn on with the default preselected, so you have to do a long button press of the top button in order to get back to viewing and selecting the other active-but-not-default profiles.

-Justin

I must have missed reading about that part

Holding the up button was all that was needed.

 

[justin_le]

'haven't read every post so pardon my laziness but is there any news about 72V/5A version mentioned on page #1?

You guys will be bummed about this but after getting the proof of concept 72V unit running in December we had our resources redirected towards a 24V 15A model after receiving some potential OEM interest in a unit with those specs. That turned out to be a lot more rework and layout redesign than expected to deal with the higher currents, so it's only just wrapped up. Potentially big volumes if it pans out, but not the kind of thing to generate aftermarket excitement here.

So, 72V stalled, but just about to restart. The moment there is a worthy update to share here then I'll post it for sure. One thing is for sure, we have the spec set to 103V max, so it will work OK with up to 24S battery packs.

 

[Alan B]

Excellent!

Glad to see progress, and ready when you are!

Just upgraded my CroBorg to 18S 32AH.

 

[Ykick]

'haven't read every post so pardon my laziness but is there any news about 72V/5A version mentioned on page #1?

You guys will be bummed about this but after getting the proof of concept 72V unit running in December we had our resources redirected towards a 24V 15A model after receiving some potential OEM interest in a unit with those specs. That turned out to be a lot more rework and layout redesign than expected to deal with the higher currents, so it's only just wrapped up. Potentially big volumes if it pans out, but not the kind of thing to generate aftermarket excitement here.

So, 72V stalled, but just about to restart. The moment there is a worthy update to share here then I'll post it for sure. One thing is for sure, we have the spec set to 103V max, so it will work OK with up to 24S battery packs.

Thanks Justin, it's always great to hear what's happening from your perspective and congratulations about the potential OEM client. Awesome!

No rush, but I'll be ready when Satiator can output up to 67.2V or more!

 

[cal3thousand]

'haven't read every post so pardon my laziness but is there any news about 72V/5A version mentioned on page #1?

You guys will be bummed about this but after getting the proof of concept 72V unit running in December we had our resources redirected towards a 24V 15A model after receiving some potential OEM interest in a unit with those specs. That turned out to be a lot more rework and layout redesign than expected to deal with the higher currents, so it's only just wrapped up. Potentially big volumes if it pans out, but not the kind of thing to generate aftermarket excitement here.

So, 72V stalled, but just about to restart. The moment there is a worthy update to share here then I'll post it for sure. One thing is for sure, we have the spec set to 103V max, so it will work OK with up to 24S battery packs.

I'm not bummed. That's great news! Great to hear that you have an OEM wanting to order 24V units. And it's also great to hear that your higher powered model will accommodate 24S! I will certainly be ordering one as soon as you have it ready.

 

[tomjasz]

Completely excited here. My Satiator is ordered. After much reading and excitement I sorted through the perceived negatives and found the Satiator to be the perfect solution to my needs SO along with a CA3 I'm all in for the Grin(s).

What an experience this was dealing with ebikes.ca. I came from years of customer service as a director for The Mirage Hotel in Las Vegas. My career was based on serving customers and I've found ebikes to be everything I want in an ebikeparts and kit supplier I am so looking forward to growing with Grin.