Zippy Flightmax / Turnigy lipo testing

[recumpence]

I agree with Methods. I am not into this for cost savings on trasportation or because I love to hug trees. I am into it as a hobby that moves us closer to electric cars and motorcycles.

It is funny how, just a year ago, even guys like Gary were pushing eveyone away from Lipo. Now many are moving toward Lipo without looking back, including those who were against it not long ago. I was pretty much told by eveybody I asked that I was insane to run Lipo in my recumbent when I started collecting parts for it less than 2 years ago. Now, here we are.

At any rate, Lipo can last a loooong time if you stay well under their C rating and stay away from over-discharging. Heck, I have an RC transmitter with a 5 eyar old lipo pack in it that is still going strong!

Matt

 

[Hyena]

The only thing stopping me from converting my car is the price of Batteries.

Likewise. Hopefully once commercial electric cars start to become more popular that'll drive the price down. That said I'll seriously look at the chevy (holden here) volt when it comes out if its not rediculously priced.
I'm sure there'll be a way to reconfigure it's battery to run the equivalent of 1/2P - 2S to make it go like a shower of shit for a short distance

I found this 3x4" vinyl gutter at Home Depot tonight. $11 for 10ft. Seems to be like what Hyena has, but ribbed.

For her pleasure!
That stuff is around 50% higher than the stuff I'm using (why must Americans supersize everything :lol: ) but its a step in the right direction for you guys in the northern hemisphere.
Incidently, I've cut and weighed a few lengths of the 100x50 stuff I'm using and am posting it to a few members in the US and Canada.
I've run out now but can buy more if there's sufficient interest. Shipping works out at $21 for 2 14" long boxes (boxes hold 4 6S packs each)

 

[mwkeefer]

For her pleasure!
That stuff is around 50% higher than the stuff I'm using (why must Americans supersize everything :lol: ) but its a step in the right direction for you guys in the northern hemisphere.
Incidently, I've cut and weighed a few lengths of the 100x50 stuff I'm using and am posting it to a few members in the US and Canada.
I've run out now but can buy more if there's sufficient interest. Shipping works out at $21 for 2 14" long boxes (boxes hold 4 6S packs each)

Guys,

The ribbed 2x3 and 3x4 I have alot of experience with (made many packs using somthing akin to the Bosch FAT packs)...

A few things...

1.) If your trying to bend it, mold it or anthing - Lowest possible oven setting and aluminum foil - the stuff just withers to nothing fast!
2.) Forget the hack saws - use Airline Snips aka Tin Snips (straight and long as possible) and drill starter holes for the cutting (dremel at really low speed works good for notch to begin cutting but.... The snips leave a much cleaner edge are really alot easier and allow you to cut to form fit (ie: around the headstem for instance) with ease.
3.) I was advised not to use a Foam cutter or any other hot tool on this, I tried it anyway ... ever burned a toothbrush for epoxy when you had no glue? Or driven past a meth lab? Yuk, don't breathe the crap.

If you sheer it along an end... you can recombine as many sections as you like for added capacity... I can't fit 10S (as 2 5S packs stacked) into a normal 2x3 but only by a narrow margin - I just cut a part 3/4 length off... did that again and joined the two long parts (first with clamps then I drilled holes and finally I used small nut/bolts (Inside of packs is insulated with 1/4" dense foam so no chance of puncture and I did get the very shortest bolts I could.

They make nice above or below main tube carriers... I don't bother making them in "chunks".. I actually Just build them for the capacity I need to length... with a little work you can make a controller mount within the conduit also (isolated from batteries) then the one nice thing... they take to paint well (a little rustoleum plastic coat serves for the flex - no cracking of paint).

The one thing I haven't tried (only thought of it a few hours ago) is low temp ironing the ridges out. I know this will be a bad thing... I will wear a o2 mask but... I have to give it a shot... If these 2x3 would flatten then they could hold 10S no prob... the 3x4 already holds 12S but not 15.

Hope that helps!

Hyena - hows about just sending me some PVC pipe from over there or find the manufacturer name for us.... I can track a source here if you can find out where its coming into market there ?

Please

-Mike

 

[hurricaniac]

Thanks again, Mike.

I'm awaiting delivery on the 48V server PSU and will report back on how it goes. My wife still insists that all lipo charging be done out in the driveway away from the house...darn those youtube videos...
-Bruce

 

[mwkeefer]

Thanks again, Mike.

I'm awaiting delivery on the 48V server PSU and will report back on how it goes. My wife still insists that all lipo charging be done out in the driveway away from the house...darn those youtube videos...
-Bruce

Bruce...

She's right. Asides from the oven (and be prepared however unlikely to loose the oven) there really aren't safe places to charge lipo in bulk indoors....

That said:

My whole plethora of supplies is next to me right now (a desk over in my bedroom) and I'm doing 3 - 3.5C charges to 80% then 2C until done. Been doing this all week = )_
I do have a trash can filled partly with Kitty Litter nearby (small trashcan) and I have a haylon extingisher (and foam for those who care)... plus, I never leave them unattended (or the iCHarger incident would have taken the house down)... until now, honestly I watched them while they charged to analyze curves at various charging rates and to see how different methods ... well, differ. Now I am convinced if your not charging outdoors, YOU MUST KEEP AN EYE on them...

I think methods puffed a cell (not exploded, I don't think) because he didn't hear the BM6 going off with the enemic beep beep beep.

And the iCharger incident I had demonstrates (it did for me)... even a nicer RC charger could burn your house down if left unattended while charging/loading indoors.

Storage:

Just use common sense... you can bring them inside when there done charging... They will be plenty safe in storage if they don't get dropped, punctured or as almost happened to me once - pre heated (My mom turned the oven on to pre-heat while I was upstairs brushing my teeth - {she was over for dinner, no i don't live with my mother! }, I came down and could smell the oven... ouch, no damage done (thank god for crappy aluminum oven plates) but that could ahve been a disaster! So if your going to use the oven for storage - do what I do... put tape over the knob. Red works well!

As you become more and more accustomed to using Lipo and more familiar with your pack (new packs are most likely to fail quickly if theres going to be an issue), your wife will too...

Sooner or later the lipo will live in the house (I think most of us on here are the same after a while, maybe it's just me.)

-Mike

 

[Hyena]

I've gotten a bit blase with my charging. I charge using only a meanwell supply in my car port now which is below my house but I often connect it after work and forget about it. I'm usually reminded when I wake up in the middle of night and hear the BM6 beeping (my bedroom window is above the carport) Theres always one cell that takes a little bit of extra charge, never above 4.23v but its enough to trip the BM6 (other cells are at 4.18v). I've got one of those battery medic balancers on the way from HK so I'll see if it behaves after balancing. I suppose after 150 cycles of never being balanced they're a bit overdue

Re: the oven, I once killed a set of car headlights by leaving them in the oven a little too long. It's the done thing to put headlights in the oven to remove the lenses if you're giving the surrounds the 'black out treatment' but yeah, I left em a little too long and came back to find droopy headlights all melted through the shelves. My then-girlfriend had some very unkind things to say about it for quite a while... :lol:

Mike I have no idea about the pipe suppliers it doesn't come with any markings or brands on it, I just buy it from our aussie equivalent of home depot (or the workbench, from the tv show reaper - if that's actually a real store!) I can send you some though, shoot me a PM.
Heating wise this stuff doesnt take much at all to go soft and floppy - I hit it for only a few seconds longer than I would normal heat shrink with my heat gun and it went like rubber. I use a cheap compound mitre saw to cut mine - same thing I used to cut the hardwood for my deck and the 3mm aluminium angle for another project The stuff is a bit brittle when cutting it though. The first length I cut was no problem but the second lot splintered, cracked and chipped a few times if I didn't go ultra slowly. It's probably just the wrong blade for the job, but beats using a dremel when I'm cutting alot of lengths

 

[El_Steak]

Quick question for all you Lipo users:

While the nominal voltage of a 24s lipo pack is 88.8v (3.7v/cell) , I see that the off-the-charger voltage is around 100v. I guess that the voltage under load falls somewhere between those numbers.

Let's say I have a 24s2p pack with 20c cells, what ballpark voltage would I get under a load of 30-40 amps?

 

[mwkeefer]

Quick question for all you Lipo users:

While the nominal voltage of a 24s lipo pack is 88.8v (3.7v/cell) , I see that the off-the-charger voltage is around 100v. I guess that the voltage under load falls somewhere between those numbers.

Let's say I have a 24s2p pack with 20c cells, what ballpark voltage would I get under a load of 30-40 amps?

I'm going to give you a bit of "unscientific" information here in the interest of simplicity.

24S2P of 20C cells wouldn't show more than a volt of dip at 30-40A so...
Full Charged Pack: 98 - 97v @ max load
Nominal: 88 - 87v @ max load
LVC: 71-70V @ max load

* read on only if you want more specific info:

---

A single parallel string of 20C cells (5AH) would be pushing 6-8 C or Capacity under 30-40A load but by paralleling you are presenting a load between 3-4C which is nothing to these cells.

A pack of 24S2P could handle current draws of 200A sustained (20C) or 300A for 15-60 seconds (30C) by using between 3 and 4 C (which will really end up being between .5 and 4C but average will be around 1.5C).

You need to assume nominal operation, these discharge in a near linear (straight progression) manor so they will progress slowly from 4.15v per cell down to between 3.8 and 3.7... once at nominal voltage they will hang there for most of their life, with a well managed and balanced pack of 24S2P (about 10 shallow cycles before actually running) you can use a cutout at about 3.3v and all cells will end up about .3v of each other at end of cycle.

So you will have a pack with the following specs:
Fully Charged (off charger): 99.6v @ 4.15v per cell
Nominal: 88.8v
Suggested LVC: 81.6v @ 3.4v
Allowable LVC: 72v @ 3.0 if cell level monitoring / LVC is implemented.
Capacity: 888 wh

I would suggest you upgrade a controller to 160v caps, FETs and and components to handle that voltage... I would ask some of the others who have done 24s (Gary, Methods, YPedal I think, LiveforPhysics, etc) to see what controller they have used and what modifications - build ups they have done.

You will be running practically US house voltage in that ride, best build up first than repair later.

 

[mwkeefer]

Quick question for all you Lipo users:

While the nominal voltage of a 24s lipo pack is 88.8v (3.7v/cell) , I see that the off-the-charger voltage is around 100v. I guess that the voltage under load falls somewhere between those numbers.

Let's say I have a 24s2p pack with 20c cells, what ballpark voltage would I get under a load of 30-40 amps?

I'm going to give you a bit of "unscientific" information here in the interest of simplicity.

24S2P of 20C cells wouldn't show more than a volt of dip at 30-40A so...
Full Charged Pack: 98 - 97v @ max load
Nominal: 88 - 87v @ max load
LVC: 71-70V @ max load

* read on only if you want more specific info:

---

A single parallel string of 20C cells (5AH) would be pushing 6-8 C or Capacity under 30-40A load but by paralleling you are presenting a load between 3-4C which is nothing to these cells.

A pack of 24S2P could handle current draws of 200A sustained (20C) or 300A for 15-60 seconds (30C) by using between 3 and 4 C (which will really end up being between .5 and 4C but average will be around 1.5C).

You need to assume nominal operation, these discharge in a near linear (straight progression) manor so they will progress slowly from 4.15v per cell down to between 3.8 and 3.7... once at nominal voltage they will hang there for most of their life, with a well managed and balanced pack of 24S2P (about 10 shallow cycles before actually running) you can use a cutout at about 3.3v and all cells will end up about .3v of each other at end of cycle.

So you will have a pack with the following specs:
Fully Charged (off charger): 99.6v @ 4.15v per cell
Nominal: 88.8v
Suggested LVC: 81.6v @ 3.4v
Allowable LVC: 72v @ 3.0 if cell level monitoring / LVC is implemented.
Capacity: 888 wh

I would suggest you upgrade a controller to 160v caps, FETs and and components to handle that voltage... I would ask some of the others who have done 24s (Gary, Methods, YPedal I think, LiveforPhysics, etc) to see what controller they have used and what modifications - build ups they have done.

You will be running practically US house voltage in that ride, best build up first than repair later.

 

[El_Steak]

Thanks for the quick and detailled answer.

You need to assume nominal operation, these discharge in a near linear (straight progression) manor so they will progress slowly from 4.15v per cell down to between 3.8 and 3.7... once at nominal voltage they will hang there for most of their life

I should not be drawing more than 8ah (80%) out of that pack on my commute. So I guess I would be staying somewhat above nominal all that time. I know that LiFePO4 goes very quickly from full charge to nominal, it seems to be more progressive with LiPo. Is there a typical Lipo discharge curve available somewhere?

I would suggest you upgrade a controller to 160v caps, FETs and and components to handle that voltage... I would ask some of the others who have done 24s (Gary, Methods, YPedal I think, LiveforPhysics, etc) to see what controller they have used and what modifications - build ups they have done.

I'm one of the lucky owners of a Methods "Gangsta" 100v / 100a 18 fets controller so I'm all covered on that side

 

[mwkeefer]

At 8ah you should be fine.... stick to the 80% rule and the Lipos will last you quite some time (with proper care and feeding).

imho - LiFePo4 (of the traditional eBike variety) has a max rating of 2-3C and huge drop under load (assuming 10AH pack 12S LiFePo4)... the discharge is as you say, quick to nominal (more like jump) but the sag you get under loads is the real limiting factor of this type of LiFePo4.

There are good LiFePo4 or LiMn packs out there... but in my limited experience (very limited, I've only tested about 5 LiFePo4 packs from various vendors) the only non LiPo chemistry which has actually worked for me for 1000s of miles is the Valence Lithium Ion (Saphion?) from my Segway i2.... These are LiMnPo (Lithium Ion Magneseum Phosphase) in nature and deliver great power in a fairly safe (albeit heavy) package.

Im sure the curve is out here... I've got plots in EagleTree of logs from actual test rides if youd like some sample data for Lipo packs... the biggest I have samples for is 15S or 62.5v (EagleTree limit).

Congratz on the methods killer controller! Having just finished an upgrade on a 9FET... I have a new found respect for Mr. Methy... Those caps are a biatch! Your right you should have no issues with that controller... I don't think he programs them wide open though (current limited), you may need to program it yourself to get the desired performance (I can only assume performance with a 40A @ 98v = 3920w / 5.25hp).

How far is your commute to work and back?

Will you charge at work?

Hope it helps,
Mike

 

[El_Steak]

Im sure the curve is out here... I've got plots in EagleTree of logs from actual test rides if youd like some sample data for Lipo packs... the biggest I have samples for is 15S or 62.5v (EagleTree limit).

Thanks, I just did an image google search on lipo discharge curve and found more graphs than I needed!

How far is your commute to work and back? Will you charge at work?

Its 7-8 miles. I am planning on charging at work so I don't have to go to 24s4p.

The new HobbyKing 4 channel charger seems like a decent solution for a charger to carry to work. Not too big or heavy. At 2.2amps per channel its a bit slow but would also allow me to use a smaller powersupply.

 

[vanilla ice]

I'd wager you would have to break up a series string to use that quad.. would be cool if you didnt!

 

[mwkeefer]

el_steak,

I don't think hobby chargers are the way to go for this... Personally I would use hobby chargers just to break in the packs with repeated shallow cycles. Then build it up.

Then get some 48v Meanwell power supplies (40-100.00) S-350-48 which should be fairly easy to modfiy for 94 v (they are only rated to 94v on the PCB... it may be an issue, you may need to do a 20S pack instead) - fechter and Gary have been helping me work out some of the current limiting issues with these and I think we will shortly have a variable current circuit mod for these series of supplies (the S-350) to get them dialed in for stable operation (maybe 400w limited).

Combine as many of these in parallel as you like or... grab a pair of 48s or a trio of 24s and connect them in series to obtain your required voltage for 24S (24 * 4.15 = 49.8v) so a pair of 48v units connected in series would be safer and work better than a single 48v modified for expanded voltage... assuming you limit to 400w.. it will be 400 / 98 = 4A which is 1/3C (roughly)... add more in parallel for higher currents charges (each supply weighs about 2 lbs).

Someone here can likely offer lots of alternatives (there are too many to enumerate, my posts are long enough as is) for turnkey charging solutions and yep you still need a balancer of some sort (im using hobby chargers for now, balancing and cycling 5 times before I build a pack into configuration - only about every 10 charges do I cut it short at 4.125v per cell and then I break down the pack into parts, wire it all up as a single 5S pack (6P5S) and run it on the balancer/charger at 5 or 10A rate (into 30A capacity) until it's done. rebuild the pack into series configuration and off you go for another 10 cycles.

A good hobby charger is the iCharger 208B+ (specifically for your 24S pack) ... you would first want to build subsections of 6 or 8S from your packs.. then parallel 2 of each subsection together (I use 4mm gold plugs but you can do as you see fit) finally throw them all on the iCharger and run it at 20A rate (1010B+ is only able to run to 10A rate) - in this case... get a 24v meanwell and tune it down to 17v for use with the iCharger (that power has to come from somewhere)...

7 - 8 miles is nothing... you won't likely need to charge at work even. The bulk charger is the safest way... (since all of us get the dread Kentucky Fried Finger or burnt to shit when we break our packs apart into parallel for charging on these hobby chargers) and if you have a balancer board / bms from Gary (or anywhere else) it should work well with the Meanwell bulk and make it a fairly simple process. Eliminating the need to break the pack apart and keeping our fingers safe.

Hope this helps!

-Mike

 

[liveforphysics]

el_steak,

I don't think hobby chargers are the way to go for this... Personally I would use hobby chargers just to break in the packs with repeated shallow cycles. Then build it up.

Then get some 48v Meanwell power supplies (40-100.00) S-350-48 which should be fairly easy to modfiy for 94 v (they are only rated to 94v on the PCB... it may be an issue, you may need to do a 20S pack instead) - fechter and Gary have been helping me work out some of the current limiting issues with these and I think we will shortly have a variable current circuit mod for these series of supplies (the S-350) to get them dialed in for stable operation (maybe 400w limited).

Combine as many of these in parallel as you like or... grab a pair of 48s or a trio of 24s and connect them in series to obtain your required voltage for 24S (24 * 4.15 = 49.8v) so a pair of 48v units connected in series would be safer and work better than a single 48v modified for expanded voltage... assuming you limit to 400w.. it will be 400 / 98 = 4A which is 1/3C (roughly)... add more in parallel for higher currents charges (each supply weighs about 2 lbs).

Someone here can likely offer lots of alternatives (there are too many to enumerate, my posts are long enough as is) for turnkey charging solutions and yep you still need a balancer of some sort (im using hobby chargers for now, balancing and cycling 5 times before I build a pack into configuration - only about every 10 charges do I cut it short at 4.125v per cell and then I break down the pack into parts, wire it all up as a single 5S pack (6P5S) and run it on the balancer/charger at 5 or 10A rate (into 30A capacity) until it's done. rebuild the pack into series configuration and off you go for another 10 cycles.

A good hobby charger is the iCharger 208B+ (specifically for your 24S pack) ... you would first want to build subsections of 6 or 8S from your packs.. then parallel 2 of each subsection together (I use 4mm gold plugs but you can do as you see fit) finally throw them all on the iCharger and run it at 20A rate (1010B+ is only able to run to 10A rate) - in this case... get a 24v meanwell and tune it down to 17v for use with the iCharger (that power has to come from somewhere)...

7 - 8 miles is nothing... you won't likely need to charge at work even. The bulk charger is the safest way... (since all of us get the dread Kentucky Fried Finger or burnt to shit when we break our packs apart into parallel for charging on these hobby chargers) and if you have a balancer board / bms from Gary (or anywhere else) it should work well with the Meanwell bulk and make it a fairly simple process. Eliminating the need to break the pack apart and keeping our fingers safe.

Hope this helps!

-Mike

The 4-way 6s charger from HC uses 4 isolated chargers, and can be very simply plugged in to charge a 24s pack in a balanced fashion. It's not a bad idea really. No risk of KFF (or KFD), and you can plug in a little deans plug and a 6s JST connector for each of the 4 packs, and the order plugged in makes no difference. Not as fast as charging with a meanwell, but it's kinda slick.

 

[El_Steak]

Thanks for the info, I really need to research more the full-pack charging approach and the GGoodrum balancing boards.

Still, I've included a little doodle of my initial idea with the 4-way HobbyKing charger. You can all bow to my 1337 MS-Paint skillz.

As mentioned by LFP, its pretty foolproof in terms of fried fingers. Each pair of Lipo 6s pack is paralled to a single connector. Those paired pack can then be connected to a serial adapter for discharge (puts them in 24s2p) or invidually to one of the HK charger output.

To avoid any risk of shorts, the connector from the serial adapter to the controller should be different than the other connectors. If using andersons, it could simply be one connector on top of the other instead of sideways.

There's still one risk though, the JST connector of a pack could be connected to a different charger channel than the pack's discharge connector. This would mean that the charger would monitor the wrong pack while charging and if the packs are really unbalanced, it could mean a nasty situation. This could probably be avoided by taping the JST connectors with their matching discharge connectors in a way that would prevent them from being mixed up.

The charger is slow (2.2amps per channel) so a full charge would take 4-5 hours. The upside however is that you only need a small (250watts) DC power supply which is another bonus for a portable charging solution.

 

[mwkeefer]

el_steak -

Seems as though you've thought this out far in advance so I won't comment on your chosen design (except to say visio has some much better tools for this type of drawing, no elite skills req.)

I went that way when I started up too... its safe proving the charger doesn't error.

I prefer (method and Hyena converted me) the meanwell method (or just CCCV power supply) because they are available, reproducable and cheap in comparison and can always be used to power the hobby balancer / charger but... to that end I'd say Fechter and Gary are no more than a week away from a final beta (and much better than any china junk imho) version due to some recent clarification (thanks Fechter) about the current limiting portion of the meanwells.

Again I did the same thing in the beginning (multiple hobby chargers on each 1/2 of a 10s (2S5S) pack) and it really did (along with watching the charge process and analyzing the discharge process via EagleTree) help me wrap my mind around the whole interrelationship of performance, efficiency, range and weight.

-Mike

 

[El_Steak]

mwkeefer,

The solution I doodled with the 4 way hobby king charger is a possible approach, but there's still some clunkiness in it with a lot of connecting / disconnecting. The fact that you went through that and moved to something else after raises a red flag for me. I will definately research the Meanwell approach more before I do anything. Thanks for leading me towards it.

I want to be sure I fully understand LiPo before I get into it. I'm in the process of reading this whole thread (+48pages ) and I am learning a lot from it. I also read the "LiPo battery care and basic information" thread which was a good starter.

My commute is actually about 9 miles one way (18 miles both) (I made an error converting km to miles). I could probably make it both ways with a 24s2p pack, but I want to use only 70-80% of the pack capacity to get it to live longer and to stay far from the LVC. I also want to ride the bike aggressively at high-amps without having to worry too much about my remaining capacity. If I move to a 3p pack I could skip recharging at work which would allow me to have a bigger stationnary charging setup at home. Would also prevent me from starting a LiPo fire in the office... which could create a bad precedent for other ebike users in my building

Will have to give it more thought.

 

[SpeedEBikes]

I switch my packs from series to parallel for doing balance charging with a hobby charger. But I don't do it very often. For my typical day to day use I bulk charge with the packs left in series. But for safety I seriously undercharge my packs when doing bulk charging. I get away with this because I have more than twice the capacity I need for my typical daily usage. Also, now due to using celllog cell monitors I monitor the voltage of every cell and it is easy to see when balancing is needed.

I could imagine a slightly improved celllog design which would always pick the highest voltage cell from which to draw it's minimal current. That combined with packs made from well matched good quality cells would mostly eliminate the need to do balance charges.

 

[voicecoils]

To match my six Flightmax 15C 5S1P packs and the one BM-6 unit I already have I grabbed the following:

1x #HKB-Medic/10328 Hobby King Battery Medic System 6S variations = $23.95
2x #BM-6/8927 BM-6 Cell Voltage Monitor 2-6S Lipo (New Version) variations = $25.90
2x #JSTMF-5S-20/9738 JST-XH 5S Wire Extension 20cm (10pcs/bag) variations = $8.44

The plan is to parallel the balance taps for the 3S2P setup together and use a BM-6 on each for voltage monitoring and lvc per cell pair warning buzzing. The 6S battery medic can then be used on each pack to discharge each cell to the same voltage then charge up all together, balanced.

The package arrived. I'm getting rattle rattle sound on the HKB-Medic dang! I'll have to decide if I want to just plug it in and risk it, open it up and see what's loose, or send it straight back.

I need to do some discharge balancing so that I can get the packs connected and put into service!

 

[Hyena]

Is it really the end of the world to undo a few screws and check ??
I would given the reputation chinese stuff has for QC.

And whats this balancing business - they should all be pretty well balanced on arrival. Belt em up to 4.15 @ 2C then go for a thrash around the block.

 

[Vanquizor]

If the hobby king 4x6s channel chargers are isolated, is there any reason a guy couldn't leave it connnected perminantly on a 24s pack? I'm thinking have it hard wired in, use a external power supply to bulk charge the pack when I need it quick and use the 4x6 to do a balance or top off charge when I need it all...

 

[vanilla ice]

I would be tempted to wire it in to the bike too. The only possible issue I can see is power drainback thru the charger.

Thats awesome the quad is isolated. The freaking $6 HC balancers aren't!! Also I think its one of the few items where the price is significantly lower if you are platinum member! I was thinking of trying meanwell next but this is so slick I'd just put up with the slowness. BTW on the Lilo setting these should charge to 4.10v for cycle life..

 

[voicecoils]

Is it really the end of the world to undo a few screws and check ??
I would given the reputation chinese stuff has for QC.

No screws on the case, does sound like a plastic rattle though. I'm just going to plug it in and see what happens.

 

[mwkeefer]

Just wire up a SP3T relay at the packs on the Ground lead for teh balancers... flip the switch to disable them so they don't consume power while connecting to the pack in storage mode.

I had thought these were not isolated though?

-Mike