Celllog 8M or 8S with 8 Bosch Fat Packs?

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ambroseliao   100 kW

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Celllog 8M or 8S with 8 Bosch Fat Packs?

Post by ambroseliao » Jul 20 2010 5:23pm

I really want to use one of these Celllogs with my Bosch Fat Packs so that I can monitor each of the 8 2S10P packs individually.

Two questions:

First, is this doable with either the M or S versions of the Celllog? The BFPs come off the charger at 41.9V and the Celllogs can read up to 43V.

Second, which one should I get. I don't think I really need the logging ability since I just want to be sure the packs are OK and ride!

I have my setup configured this way right now:
8 BFP Series-Parallel 36-72V battery switch 4pdt configuration.jpg
8 BFP Series-Parallel 36-72V battery switch 4pdt configuration.jpg (74.16 KiB) Viewed 1042 times
The Celllogs are here:
The 8M - http://www.hobbyking.com/hobbyking/stor ... duct=10952
The 8S - http://www.hobbyking.com/hobbyking/stor ... oduct=9282

They seem to be a terrific deal for what they offer (IF they can work with my setup!)

Thanks for any info.

Ambrose
http://www.ebikes.ca/ is the best!

TidalForce M-750X, Tidalforce S-750 with Crystalyte HS3540, 1x TF iO-X Cruiser. E+ 1000W hybrid bike. ebikes.ca DrainBrain & Cycle Analyst meters. GoPro HD Hero2 camera. Bosch Fat Packs, 37V 10Ah LiPO pack. Turnigy Multistar batteries
My blog: http://ebikerider.blogspot.com
Remember LiFEPo4 HVC is 3.65V and LVC is 2.7V

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Re: Celllog 8M or 8S with 8 Bosch Fat Packs?

Post by icecube57 » Jul 21 2010 10:41pm

Rethink using that switch. I thought it would be a cool idea also but those contacts on the bottom are way to close for comfort and dealing with that voltage and unadulterated amperage scares me SHEITLESS... I would rather monitor the sub sections with a Turnigy Watt Meter than a cell log. It would be intresting to see how you tap all the points in the packs to monitor voltage if you do decide to use it unless you just want to look at full pack voltage and not individual cell voltages. I still think a Turnigy Watt Meter is what you want.

Please tell me if you are using a fuse on the pack. You will need them with that switch.

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Re: Celllog 8M or 8S with 8 Bosch Fat Packs?

Post by mwkeefer » Jul 21 2010 11:23pm

ambroseliao wrote:I really want to use one of these Celllogs with my Bosch Fat Packs so that I can monitor each of the 8 2S10P packs individually.
So you want to monitor:
Each (8 individual) of the 36v Bosch Toolpacks in your current 36v/72v switched Power Source for voltage..

And you want to do this with:
1 x CellLog 8S/8M?
ambroseliao wrote: Two questions:

First, is this doable with either the M or S versions of the Celllog? The BFPs come off the charger at 41.9V and the Celllogs can read up to 43V.
Doable yes - as you describe or I interpret... No not with a single CellLog8..
ambroseliao wrote: Second, which one should I get. I don't think I really need the logging ability since I just want to be sure the packs are OK and ride!

You are getting more and more advanced... if the CellLog8 works out for your purpose, once we decode and see how far you want to go... Get the logging / usb version, you will eventually want to log the trend and cliff point on your pack in detail, graphed... they do it, also the firmware is updateable on these :)_... well worth the extra 9$.
ambroseliao wrote:
I have my setup configured this way right now:
8 BFP Series-Parallel 36-72V battery switch 4pdt configuration.jpg
The Celllogs are here:
The 8M - http://www.hobbyking.com/hobbyking/stor ... duct=10952
The 8S - http://www.hobbyking.com/hobbyking/stor ... oduct=9282

They seem to be a terrific deal for what they offer (IF they can work with my setup!)

Thanks for any info.

Ambrose
I have a way you could maintain the switch (but you would need to pick a default mode, I would suggest 36v8P as the default mode) but must implement some relays to link the 36V parts into parallel (Normally Closed) and then Switch those off... before switching on the Series Relays to make a 74v pack.

The other thing... 36v Bosch Packs are 10S as I listed above so while you could monitor the pack voltage as a whole and set alarms at that level, cell level logging would require modification of each pack to expose a pair of 5S balance connectors which you would then parallel with gary goodrums HVC/LVC or parallel adapter since you have an existing BMS in the tool packs... That would be 2 x 8 for the 5S baalnce connectors... this would allow you access to 5S at a time so 2 cell loggers could monitor 72v..

Trick would come by going to 72v... these would need a low current 9PDT (or multiple SP) to shift the right 4P section's balance lines to 2 additional CellLog8s which would then monitor the remaining 2 x 5s introduced by reterminating Series.

Also... your controller will require an any voltage mod using either switching (I think you use Lyen controllers, check even if it's a switcher that it can support the range with a single Resistor selection) or the old tried and true method of replacing R1A with a Tip122 transistor good from 36 to 100v and a few other parts - knuckles and methods both cover this...

If your goal were an Apple Computer Laptop style method of checking the packs voltage range at a given moment, they would need to be isolated from each other or your getting the voltage of the parallel block and not detecting a low cell in the block...

What is the end goal of using the cell logs with the Bosh Packs? You again could monitor the 2 parallel banks of primary 36v using a pair of cell log8s (second is need when going to 72v mode or only 1/2 the pack would be monitored...

A little more info on your end game would help me to point you further in your quest.

Hope it helps!

-Mike
Regards,
Mike

{My Rides]
2010 Dahon Jack - GNG v1 - LYEN 6FET - 20/40A - 18S2P10AH - Nom:66.6v,1332w
2004 Hard Rock Pro Disc - Recumpence ms eDrive v4 - Astro 3220 4T - 12S2P16AH - HV110 - Left Side Drive - Gearing: 38mph
Nominal Peak Power @ 60 seconds: 5328 watts - Maximum Power: 49.8v, 120A, 5872w
2010 Downtube 8FH - Stock GNG v1 Stock Controller - EB809XC - 12-16S
2012 Downtube Nova 7spd - Stock GNG v2 - 12S2P10AH - EB809 - 12S-16S - 20A/30A,Nom VCC: 44.4, 888w

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ambroseliao   100 kW

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Re: Celllog 8M or 8S with 8 Bosch Fat Packs?

Post by ambroseliao » Jul 22 2010 8:56am

icecube57 wrote:Rethink using that switch. I thought it would be a cool idea also but those contacts on the bottom are way to close for comfort and dealing with that voltage and unadulterated amperage scares me SHEITLESS... I would rather monitor the sub sections with a Turnigy Watt Meter than a cell log. It would be intresting to see how you tap all the points in the packs to monitor voltage if you do decide to use it unless you just want to look at full pack voltage and not individual cell voltages. I still think a Turnigy Watt Meter is what you want.

Please tell me if you are using a fuse on the pack. You will need them with that switch.
Thanks Ice,

I would definitely separate all of the connectors with some kind of insulator and install a fuse. I would probably shrinkwrap every connector so minimize shorts.

Ambrose
http://www.ebikes.ca/ is the best!

TidalForce M-750X, Tidalforce S-750 with Crystalyte HS3540, 1x TF iO-X Cruiser. E+ 1000W hybrid bike. ebikes.ca DrainBrain & Cycle Analyst meters. GoPro HD Hero2 camera. Bosch Fat Packs, 37V 10Ah LiPO pack. Turnigy Multistar batteries
My blog: http://ebikerider.blogspot.com
Remember LiFEPo4 HVC is 3.65V and LVC is 2.7V

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Re: Celllog 8M or 8S with 8 Bosch Fat Packs?

Post by ambroseliao » Jul 22 2010 10:59pm

mwkeefer wrote: I have a way you could maintain the switch (but you would need to pick a default mode, I would suggest 36v8P as the default mode) but must implement some relays to link the 36V parts into parallel (Normally Closed) and then Switch those off... before switching on the Series Relays to make a 74v pack.

The other thing... 36v Bosch Packs are 10S as I listed above so while you could monitor the pack voltage as a whole and set alarms at that level, cell level logging would require modification of each pack to expose a pair of 5S balance connectors which you would then parallel with gary goodrums HVC/LVC or parallel adapter since you have an existing BMS in the tool packs... That would be 2 x 8 for the 5S baalnce connectors... this would allow you access to 5S at a time so 2 cell loggers could monitor 72v..

Trick would come by going to 72v... these would need a low current 9PDT (or multiple SP) to shift the right 4P section's balance lines to 2 additional CellLog8s which would then monitor the remaining 2 x 5s introduced by reterminating Series.

Also... your controller will require an any voltage mod using either switching (I think you use Lyen controllers, check even if it's a switcher that it can support the range with a single Resistor selection) or the old tried and true method of replacing R1A with a Tip122 transistor good from 36 to 100v and a few other parts - knuckles and methods both cover this...

If your goal were an Apple Computer Laptop style method of checking the packs voltage range at a given moment, they would need to be isolated from each other or your getting the voltage of the parallel block and not detecting a low cell in the block...

What is the end goal of using the cell logs with the Bosh Packs? You again could monitor the 2 parallel banks of primary 36v using a pair of cell log8s (second is need when going to 72v mode or only 1/2 the pack would be monitored...

A little more info on your end game would help me to point you further in your quest.

Hope it helps!

-Mike
Mike,

The switch I'm using has a center off position so that there would be no direct switching between 37 and 74V. There would be a disconnect from 37V before the switch can go to 74V. I'm not looking for cell level logging since the Sony/Konions are relatively bulletproof. I'm looking for pack voltages to spot potential problems with any individual cells and the CellLog seems like a perfect candidate for this job. I don't need to use 37V with my 72V Lyen's controller. I need the switch so that I can charge at 37V and then flip the switch and run at 74V.

Your solution sounds technically strong, but tough for me to implement. I try very hard to keep the ebike as simple as possible which is why I like BFPs so much. They don't need a BMS to run, but I would love to have an alarm and meter on them just in case they start acting up.

You bring up a good point about the CellLog. They can't bridge the pack between 37 and 74V. I will need two CellLogs in order to use it in 74V mode, however, that would allow me to add additional BFPs if I wanted additional range.

Thanks Mike, your questions have cleared up some thoughts in my head and I appreciate your help.

Ambrose
http://www.ebikes.ca/ is the best!

TidalForce M-750X, Tidalforce S-750 with Crystalyte HS3540, 1x TF iO-X Cruiser. E+ 1000W hybrid bike. ebikes.ca DrainBrain & Cycle Analyst meters. GoPro HD Hero2 camera. Bosch Fat Packs, 37V 10Ah LiPO pack. Turnigy Multistar batteries
My blog: http://ebikerider.blogspot.com
Remember LiFEPo4 HVC is 3.65V and LVC is 2.7V

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Re: Celllog 8M or 8S with 8 Bosch Fat Packs?

Post by mwkeefer » Jul 22 2010 11:52pm

Ambrose,

** Edited:

I double checked the CellLog8's user manual and you could combine two of them, one each wired to your parallel (4P) set of packs, these would connect:

Left Bank 36v
Negative -> CellLog8 #1 - Pin #1
Positive -> CellLog8 #1 - Pin #2

Right Bank 36v
Negative -> CellLog8#2 - Pin #1
Positive -> CellLog8#2 - Pin #2

This will work fine but will only give you 36v4P level voltage display and monitoring...
Regards,
Mike

{My Rides]
2010 Dahon Jack - GNG v1 - LYEN 6FET - 20/40A - 18S2P10AH - Nom:66.6v,1332w
2004 Hard Rock Pro Disc - Recumpence ms eDrive v4 - Astro 3220 4T - 12S2P16AH - HV110 - Left Side Drive - Gearing: 38mph
Nominal Peak Power @ 60 seconds: 5328 watts - Maximum Power: 49.8v, 120A, 5872w
2010 Downtube 8FH - Stock GNG v1 Stock Controller - EB809XC - 12-16S
2012 Downtube Nova 7spd - Stock GNG v2 - 12S2P10AH - EB809 - 12S-16S - 20A/30A,Nom VCC: 44.4, 888w

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Re: Celllog 8M or 8S with 8 Bosch Fat Packs?

Post by mwkeefer » Jul 23 2010 4:41am

Ambrose,

A little more time and reading your response twice and just a few more comments (but not the type to be added to the existing response - miaculpa).
Ambrose wrote: The switch I'm using has a center off position so that there would be no direct switching between 37 and 74V. There would be a disconnect from 37V before the switch can go to 74V.
Got it, so XPDT Center Off :) That should prevent any chance of shorting going from 37 -> 74 (shorting shouldn't be possible from 74 -> 37v just FTY)
Ambrose wrote: I'm not looking for cell level logging since the Sony/Konions are relatively bulletproof.
From what I hear the cells themselves are fairly bullet proof, toolpacks in general the BMSes seem to give some people issues... the charging is what goes goofy on the rest - seems your switch is designed / intended not for the purpose of giving you 2 different maximum speed and thus efficient speed ranges of say 20mph and 40mph but only to facilitate easier charging, retention of factory BMS and simplicity and so on... I can't argue with you here!
Ambrose wrote: I'm looking for pack voltages to spot potential problems with any individual cells and the CellLog seems like a perfect candidate for this job.
This is the thing I don't get...

Either you mean individual pack voltages (meaning toolpack 36v 1P readings so 8 in all) but you indicate it's to look for potential problems with any individual "cells" - if by Cells you mean 36v Pack in 1P = 1 Cell okay... If however you mean to spot possible issues within one or another of the Series of 10 cells inside each 36v pack... well that would require bringing out balance taps or wires to get a reading on each cell voltage...

The problem is once you have these Packs in 4P configuration... the best monitoring, display or logging you can do without adding balance taps is:

4P pack level voltage, but you can't guess the cell voltages from this (divide by 10 doesn't do the trick really) and since it has no use for your charging mode of 8P (I assume) you really just get pack level voltage.

Since your goal seems that you want to potentially identify faulty cells, I have some ideas on how you could acheive just this but... they could be complicated to some extent and I don't want to go too deep but I will say that I do agree with the idea and concept - it provides you a chance to yank a bad sub pack and it's mate and keep on going - if you id it in time.
Ambrose wrote: I don't need to use 37V with my 72V Lyen's controller. I need the switch so that I can charge at 37V and then flip the switch and run at 74V.
I figured this out finally as elaborated on above... the advantage of this type of system (I'm working one out for 12/24s now) is that your setup may be good for 22mph efficiently at 36v which is enemic but has much better range usually and also is good for throttle tractibility around towns and residential neighborhoods... flipping to 74 volts and the throttle becomes a gun shy child and current draw is enormous off the line... startup in 36v until taper off, flip to 74v when you need the high end speed..

Your Lyen controller could be adapted fairly easily to work from 29v -> 100v (though 98 is the highest I will go) using Knuckles Any Voltage Mod (a Transistor a few diodes and a resistor in place of R1 inside the controller)... then you engage either voltage mode and the controller just keeps on trucking...

This is obviously not what you were after but it would be a nice possible side effect and not difficult to implement.
Ambrose wrote: Your solution sounds technically strong, but tough for me to implement. I try very hard to keep the ebike as simple as possible which is why I like BFPs so much. They don't need a BMS to run, but I would love to have an alarm and meter on them just in case they start acting up.
Thank you - I gave it some thought, just not enough :)

Since there is no way to monitor individual 10S packs voltage levels but only the parallel packs as a whole - the only way you would see an issue would be if a pack flat out failed due to internal BMS... Is that what your thinking, that a pack will cutout and drop to 0v via internal BMS and you want notification of this and some feedback / warning?

Does the internal BMS shut the output of the pack down if the voltage sags too far or a cell is below LVC?
When shutdown, does it interrupt the series connection or leave it in place?

I would assume if you lost 1/4 of your capacity (4P, 1 pack down = 1/4) that if you have a total of 10AH that would be a 2.5AH drop and should result in the effected cluster of 36v via 4P to drop by roughly 25% immediatly...

So assume nominal voltage is currently displayed on Bank #1 (Cell Log #1 Pack #1) and suddenly the voltage drops from 37v down to between 35v and 27.75 but Bank #2 is showing 36v... strong indicator you lost a pack or there is a weak pack... which one, that would require alot more work (doable but more work).
Ambrose wrote: You bring up a good point about the CellLog. They can't bridge the pack between 37 and 74V. I will need two CellLogs in order to use it in 74V mode, however, that would allow me to add additional BFPs if I wanted additional range.
They are powered by each 36v subpack so... being isolated they will work in both 37 and 2x for 74v mode... yep 2 cell log8s (and trust me get the logging ones for a few bucks more) (and you do need that for seeing possible loss of 1 of 4 in parallel of any sub pack of BFPs)...
Ambrose wrote: Thanks Mike, your questions have cleared up some thoughts in my head and I appreciate your help.
Anytime... you know that man :)

One thing... loose the switch :)

Reconfigure using a 24v coil relay DPDT Normally ON of 60-whatever Amp Rate (or multiple in parallel)...
Rewire so your 2 banks of 36v fat packs are connected in series using these DPDT NO position.. so 74v becomes the norm (since your not interested in switching back and forth) - the relay will handle the current load with little resistance so no worries there...

Wire it so that when the 42v charge supply is connected it energizes the DPDT relay and disconnects the Series Connection... while establishing the parallel connection between the 2 banks of 4Packs4Parallel...

This means it will auto switch to 36v mode for charging and then back to 74v mode when charge is complete or charger is removed...

It will also handle the discharge current in a small package and one where the power to engage the charge mode is handled via simply connecting the charger power :)

That may perhaps be the sweetest feature I've come up with for these yet...

I think I wil need to get some of these, they are what 2.3AH each pack? So I would need just 4 Packs for 40+ mi range @ 20mph and 20+ mi range @ 35-40 ish depending on sag.. What's the sag under load like on them? What are the C ratings (any ideas? - how many amps can each single tool pack deliver?)

I assume besides keeping it simple, you don't want to add balance lines because don't these carry some form of replacement warranty so long as they are not modified / opened?

That would be a big plus towards me picking some up for the customers ride... just have to use whatever type of tools they normally use :)

Hope I've been helpful and not just more confusing and thanks in advance for the feedback!
-Mike
Regards,
Mike

{My Rides]
2010 Dahon Jack - GNG v1 - LYEN 6FET - 20/40A - 18S2P10AH - Nom:66.6v,1332w
2004 Hard Rock Pro Disc - Recumpence ms eDrive v4 - Astro 3220 4T - 12S2P16AH - HV110 - Left Side Drive - Gearing: 38mph
Nominal Peak Power @ 60 seconds: 5328 watts - Maximum Power: 49.8v, 120A, 5872w
2010 Downtube 8FH - Stock GNG v1 Stock Controller - EB809XC - 12-16S
2012 Downtube Nova 7spd - Stock GNG v2 - 12S2P10AH - EB809 - 12S-16S - 20A/30A,Nom VCC: 44.4, 888w

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ambroseliao   100 kW

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Re: Celllog 8M or 8S with 8 Bosch Fat Packs?

Post by ambroseliao » Jul 25 2010 12:38am

Thanks Mike,

Your very thoughtful response is really appreciated. It's 1:30 AM here and I need to get to bed. I will reply probably early next week when I have a chance to digest all of your ideas!

Thanks,
Ambrose
http://www.ebikes.ca/ is the best!

TidalForce M-750X, Tidalforce S-750 with Crystalyte HS3540, 1x TF iO-X Cruiser. E+ 1000W hybrid bike. ebikes.ca DrainBrain & Cycle Analyst meters. GoPro HD Hero2 camera. Bosch Fat Packs, 37V 10Ah LiPO pack. Turnigy Multistar batteries
My blog: http://ebikerider.blogspot.com
Remember LiFEPo4 HVC is 3.65V and LVC is 2.7V

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Re: Celllog 8M or 8S with 8 Bosch Fat Packs?

Post by docnjoj » Jul 25 2010 9:46am

Hey Mike
Fatpacks have 60 amp fuses so that says something. I would feel safe at 8-10C but never use that much as I want them to last. I think they can do more, like DocBass's setup. I parallel 4 of them and run 2 at 18V mod for 54 volt 8ah and can get 18-20 miles if I take it easy on the throttle, I usually run about 4 ah for 14 miles @ 54 volts. Sorry but I never remember the W/H used. John in CR can tell you much more. I love their simplicity and robustness.
otherDoc
E-bike stable at our house

Steintrike Mad Max full suspension trike rear Cute 100H going on: Whoops, Cute wheel broke but I fixed it.
Sun USX delta trike EbikeKit small geared front wheel sort of front suspension for wife

Agniusm/A123 AMP 20 36 volts on the Steini has been taken off.
2x16000 Multisport from HK now gone as they died after 2 years
New Luna 10S bottle battery 13.6AH now on mine
Relatively New 10S4Px2 for wife's bike giving 20ah @ 40 volts home made Panasonic from Tumich. BMS's rule.

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