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DRZ400
22 April 2011, 0913
So I have 5 cycles on my Calib cells so far with no BMS (Celllog-Ms' on back order). I carefully bulk charged to ~3.5v then single cell charged to 3.65v. I've been limiting my rides to 15AH used so far, amazing how in charging damn close to exactly what was used is put back....I would have expected some loses. In my case with a 5amp charger, 3 hours till first cell hits 3.6v after a 15AH ride. Even though I balanced them prior to, they are definately drifting apart. 4-5 cells always hit 3.65 while most of the rest are at 3.5 - 3.55. I guess I have to be the BMS for the time being...limit 2 30ah ride and check the "hot" cells during the last 15 minutes of charging.

frodus
22 April 2011, 1020
nice..... ride video?

ZoomSmith
22 April 2011, 1551
I'm hoping that "Bareback" refers to no protection (for your cells)? If so, please post pics. Otherwise, I'm sure we don't want to know the details behind the title. ;-)

DRZ400
22 April 2011, 1650
Of course sans BMS.... its interesting to see how quickly a cell can go from 3.5 to 3.6 plus in just a few minutes @ a 5amp charge.....while others are at ~ 3.45 volts. Makes me wonder where the non bms crowd buys thier magical cells? The low end is much easier to watch, just use 80% of you capacity and set your controll for a higher LVC. But during charging you need to be on it. I guess if you had a programmable charger you could just charge what you used? That may work for a while, but given what I've seen I suspect the cells will slowly imbalance and cause a problem.

chef
22 April 2011, 1846
There's very little energy charging from 3.45-3.65v. People who don't use a BMS set the pack HVC to an avg of 3.4-3.5v per cell. This assumes that the cells aren't too far apart.

Once you bareback, you never go back :P

ZoomSmith
22 April 2011, 1924
Adding a 25th cell will put you in the 3.44 neighborhood, a safer place to hang out bareback.

DRZ400
22 April 2011, 2002
yeah, i use 3 24v 5amp chargers, my first charge i had an 8amp diode in series with each charger....about a 2.2 volt drop total. adding a cell sounds like a good idea...

i do like the idea of having the individual v levels that the celllog provides

DRZ400
22 April 2011, 2006
There's very little energy charging from 3.45-3.65v. People who don't use a BMS set the pack HVC to an avg of 3.4-3.5v per cell. This assumes that the cells aren't too far apart.

Once you bareback, you never go back :P

true on both counts....it only takes my cells a few minutes to go from 3.5 to 3.6, can't be much energy there.

DRZ400
08 May 2011, 0913
Got about a dozen cycles so far on the Calibs, last two I took to 30AH, was still able to maintain 60 mph with very little voltage sag. I have about .14 volt delta between high and low cells after the first cell hits 3.6v so they appear to be pretty stable. Should have my backordered cellogs next week.

frodus
09 May 2011, 0759
I've actually seen quite a bit of energy go into a cell after 3.4V, but if you set the charger at 3.45V compared to 3.65V, the 3.65V will put the same energy in, but it'l go a bit faster. The higher the voltage the more the "pull" from the charger.

So not a difference in energy, more of a difference in speed of charging.

And that was done on my bench with an adjustable power supply. I should actually compare two, discharge them the same amount, and then charge one at 3.45 and the other at 3.65V.

billmi
10 May 2011, 1246
Sounds like the switch to lithium has been good for you. Are you planning to add a MiniBMS, or just go with alerts from the Cell-Logs? I didn't mess with balancing my pack, and by the 20th cycle or so, the MiniBMS had brought it into balance close enough that the charger is shutting itself off from pack level, rather than cell level HVC from the MiniBMS.

I just took a 22 mile round trip for lunch today (favorite downtown pubs and restaurants all comfortably in range) and for the first time came in under 80 Wh/Hr per mile, at 79 :-) With traffic in the city there ended up being a lot more coasting and sub-speed limit riding than when I'm just holding speed out here on the more rural side of town. Simply loving it.

DRZ400
10 May 2011, 1259
Yes, love the Calibs so far. I've been limiting my discharge to 30ah's (~25miles)....I rarely got more then 15ah's out of the SLA's, plus my top speed is the same throughout. With the SLA's my speed would start to drop from the start. Last night I pulled out my Turnigy 8 cell balance charger and balanced them as 3 banks after bulk charging to first cell of 3.6v. Took about 1 hour each bank, the turnigy has a .3 amp balance current I think. I'll probably go Mini BMS as checking cell charge time and voltage is getting old. My back ordered Cellogs are on the way. I sold my 3 year old SLA's to a buddy with a trolling boat, he says they perform as new....just goes to show that SLA's are more often murdered and don't die when properly used.

DRZ400
11 May 2011, 0709
I bulk charged again yesterday till the first of 24 cells hit 3.6 volts, then I put the turnigy charger on 3 of 8 cell banks to balance them (nice having the JST-8 connector for cellogs or charger). Several cells were in the low 3.4 several in the low 3.5. Each bank took about 2-3 hours to balance but the charger only put in about 500-600 mah. I expected much higher...the Turnigy started out at 2amp but downshifted to .2 .1 amp pretty quick. Seems like even though the voltage delta was ~.150 the capacity difference was very, very small.

EVcycle
11 May 2011, 1558
Bareback is the only way to go......

Until I see a better BMS anyway! :)

DRZ400
11 May 2011, 1728
I ordered the mini-bms...but so far my experiance has been the cells stay very close....as long as you balance first and count ah during the ride and charge.

EVcycle
11 May 2011, 1738
Not to be a party pooper, but I have to run in the rain as well as heat and the elements do a job on electronics.

The problem is that a motorcycles get....um wet. I have tired to keep things simple due to this.
Cars are one thing, but unless you have it all water tight, you will eventually have an issue.

Hence the lack of a on board charger and a BMS on our bikes.....for now.

I am sure there are some systems out there that are all weather, but they are expensive...

For Now the KISS system is for us.

jpanichella
11 May 2011, 1740
I ordered the mini-bms...but so far my experiance has been the cells stay very close....as long as you balance first and count ah during the ride and charge.

Cool. Tell us how you like it when it's hooked up.

jpanichella
11 May 2011, 1745
Not to be a party pooper, but I have to run in the rain as well as heat and the elements do a job on electronics.

The problem is that a motorcycles get....um wet. I have tired to keep things simple due to this.
Cars are one thing, but unless you have it all water tight, you will eventually have an issue.

Hence the lack of a on board charger and a BMS on our bikes.....for now.

I am sure there are some systems out there that are all weather, but they are expensive...

Fir Now the KISS system is for us.

Dimitri said that every minibms board is clear coated and are water resistant, not waterproof. He said that he had one costumer report a failure due to water, but there was water actually accumulating on top of his terminals. I think that a simple plexiglass cover that keeps the terminals and BMS modules from getting too wet, but who knows what might happen in a violent downpour.

EVcycle
11 May 2011, 1749
I use the cell log too and love it. The connections are one of my concerns as well.

Wires and water do not make a good mix. :(

DRZ400
11 May 2011, 1759
u mean minibms not cellog and dimitri


Dimitri said that every cell-log is clear coated and are water resistant, not waterproof. He said that he had one costumer report a failure due to water, but there was water actually accumulating on top of his terminals. I think that a simple plexiglass cover that keeps the terminals and BMS modules from getting too wet, but who knows what might happen in a violent downpour.

jpanichella
11 May 2011, 1806
u mean minibms not cellog and dimitri

Yup, I edited the original post. Thanks for the correction

billmi
12 May 2011, 0933
Dimitri said that every minibms board is clear coated and are water resistant, not waterproof. He said that he had one costumer report a failure due to water, but there was water actually accumulating on top of his terminals.

Funny, he told me exactly the same thing :-)



I think that a simple plexiglass cover that keeps the terminals and BMS modules from getting too wet, but who knows what might happen in a violent downpour.

That's been my approach - a splash or drip or two doesn't concern me so much as an area where water might collect and then flow as a steady stream. My charger and the tops of my 8 cell bank (and MiniBMS modules) are well up under the tank. My two batteries in the rear are sheltered on top by the seat and have a lexan wraparound cover. My box of 14 cells in front of the motor have their terminal side rear-facing to minimize road splash, and that is covered by a (not sealed) acrylic sheet. On top of them is an acrylic sheet sealed to their bracket with silicone to prevent collecting and dripping. My Cycle Analyst is sealed in the dash. My controller is sealed waterproof (I figured with Florida weather that was worth the extra $35).

I wouldn't say my whole bike is waterproof, but I think it's well suited to handling a ride in the rain without anything sensitive falling prey to water. That said, if I know it's going to rain, I'm riding a DR-200 anyway (unless I wuss out and take the car) the trail tires like the wet better than the street tires on the Ninja.

jpanichella
12 May 2011, 0959
Funny, he told me exactly the same thing :-)



That's been my approach - a splash or drip or two doesn't concern me so much as an area where water might collect and then flow as a steady stream. My charger and the tops of my 8 cell bank (and MiniBMS modules) are well up under the tank. My two batteries in the rear are sheltered on top by the seat and have a lexan wraparound cover. My box of 14 cells in front of the motor have their terminal side rear-facing to minimize road splash, and that is covered by a (not sealed) acrylic sheet. On top of them is an acrylic sheet sealed to their bracket with silicone to prevent collecting and dripping. My Cycle Analyst is sealed in the dash. My controller is sealed waterproof (I figured with Florida weather that was worth the extra $35).

I wouldn't say my whole bike is waterproof, but I think it's well suited to handling a ride in the rain without anything sensitive falling prey to water. That said, if I know it's going to rain, I'm riding a DR-200 anyway (unless I wuss out and take the car) the trail tires like the wet better than the street tires on the Ninja.

I forgot that was your thread on DIYElectricCar (the EV building community is so small sometimes it's ridiculous).

In terms of your Kelly controller being waterproof, read this:

http://endless-sphere.com/forums/viewtopic.php?f=12&t=27091

My plan is to seal the batteries with acrylic covers (similar to what Noah did), and have covers on the controller and all of the major electrical components. I'm going to try and pretty much seal everything I can. I don't plan on riding in the rain much, but I have some ideas to make my bike fairly water resistant.

DRZ400
16 May 2011, 0617
About to start riding with protection....got my minibms units from Dimitri, very nicely made. I like that it has temperature comp on lvc, ptc fuse one the shunt and a simple nc loop. Guy makes a nice, inexpensive unit. New charger also came from bmsbattery, 86v, 6amp....missed the DHL truck however.

billmi
16 May 2011, 1213
Excellent! I really like the affordable pricing and the features of the MiniBMS. I soldered a bullet connector to each MiniBMS, and 3 of them got two bullet connectors, that way I could tap the Cell-Logs right off of them, to check individual cell voltages.

BTW, I've had a couple of LVC events on the MiniBMS due to voltage drop while riding - each was under a second in length after accelerating for several seconds with the throttle wide open. With the MiniBMS wired into the throttle my acceleration slowed for a moment, then picked right back up as the voltage recovered - pretty much self correcting.

jpanichella
16 May 2011, 1217
Excellent! I really like the affordable pricing and the features of the MiniBMS. I soldered a bullet connector to each MiniBMS, and 3 of them got two bullet connectors, that way I could tap the Cell-Logs right off of them, to check individual cell voltages.

BTW, I've had a couple of LVC events on the MiniBMS due to voltage drop while riding - each was under a second in length after accelerating for several seconds with the throttle wide open. With the MiniBMS wired into the throttle my acceleration slowed for a moment, then picked right back up as the voltage recovered - pretty much self correcting.

Sounds like it's working perfectly for you. Seems like for the price MiniBMS can't really be beat.

DRZ400
16 May 2011, 1357
Really? How many ah into discharge were you? I guess theres no way to tell which cell(s).


Excellent! I really like the affordable pricing and the features of the MiniBMS. I soldered a bullet connector to each MiniBMS, and 3 of them got two bullet connectors, that way I could tap the Cell-Logs right off of them, to check individual cell voltages.

BTW, I've had a couple of LVC events on the MiniBMS due to voltage drop while riding - each was under a second in length after accelerating for several seconds with the throttle wide open. With the MiniBMS wired into the throttle my acceleration slowed for a moment, then picked right back up as the voltage recovered - pretty much self correcting.

billmi
17 May 2011, 0837
Really? How many ah into discharge were you?

Somewhere around 8ah, each time. Keep in mind, these haven't happened during normal street riding, just when running 0 to 50 with the throttle at 100% the whole way. Traffic doesn't usually allow that (i.e. a car in front of me).


I guess theres no way to tell which cell(s).

Unfortunately no, since I got the cheaper Cell-Logs without the logging option. It's not a serious concern for me, as it's not caused a serious problem (I kept accelerating, just slowed a bit) and has only happened in two out of some 30-40 battery cycles, and only then under a style of riding that is atypical for me.

jpanichella
17 May 2011, 0856
Somewhere around 8ah, each time. Keep in mind, these haven't happened during normal street riding, just when running 0 to 50 with the throttle at 100% the whole way. Traffic doesn't usually allow that (i.e. a car in front of me).



Unfortunately no, since I got the cheaper Cell-Logs without the logging option. It's not a serious concern for me, as it's not caused a serious problem (I kept accelerating, just slowed a bit) and has only happened in two out of some 30-40 battery cycles, and only then under a style of riding that is atypical for me.

Do you keep your cell logs in your main "c-ockpit" or do you just use them to monitor charging? Are they always on? Or do they come on when you switch on the ignition circuit on the MiniBMS?

edit: can't say c-ockpit apparently.

billmi
17 May 2011, 0910
At the moment I keep them in a box on my workbench, and plug them into their wiring bundles on the bike when I want to check cell voltages. On my to-do list is building a housing that will hold all three of them, and finding a good place for it on the bike. The Cell-Logs have an adjustable "sleep" time out, after which they will go dormant (draw almost no power) until one of their buttons is pressed.

DRZ400
17 May 2011, 0919
Yeah, I bought 3, 8-cell JST connectors with 2' silicon wires from ebay. I just plug in a cell-log or my TC balance charger when needed. Once I have the minibms on, I shouldn't need the balance charger anymore. Good to know about the sleep mode, I didn't know that.

jpanichella
17 May 2011, 0940
Something like this?

http://cgi.ebay.com/7S-JST-XH-Connector-balance-wire-Cell-Log-8-PIN-8pin-/130422862588?pt=Radio_Control_Parts_Accessories&hash=item1e5dcef2fc#ht_2124wt_923

DRZ400
31 May 2011, 1035
That would be them!


Something like this?

http://cgi.ebay.com/7S-JST-XH-Connector-balance-wire-Cell-Log-8-PIN-8pin-/130422862588?pt=Radio_Control_Parts_Accessories&hash=item1e5dcef2fc#ht_2124wt_923

DRZ400
31 May 2011, 1044
I haven't put in the mini bms yet, been chargring with 3 diodes in sieres with 86.4v charger. My charger stops with cells being between 3.45 - 3.5 volts. Thought occurs that if I add 1 cell and remove the diodes that I'd get a couple mph more speed with about the same SOC. I have 4 headways that I could parallel to make 1 more 3.3 40ah cell. If it works as expected will order another calib.

billmi
22 June 2011, 1201
Have you dropped in the BMS yet? If so, how's it doing?

DRZ400
22 June 2011, 1525
no, still riding bareback. I did add a 25th cell, 1s4p headway. Gives me 3mph more on top, max of 65 mph now. a full charge puts me in the 3.45 - 3.5 range although the cells definately drift....one hit 3.6 the other day, so much like my teen years unwatched bareback could lead to trouble.

EVcycle
22 June 2011, 1616
Single chargers will fix that.

:)


Bareback Ed

DRZ400
22 June 2011, 1711
Sorry Ed, you ain't bareback with single cell 3.6 volt chargers (top end protection (assuming you're talking about your headways)). I use my bike too much too only charge at 2 amps.....even 6 amps is marginal. At least with Li's I can now do a partial charge if I want to ride...were as with lead I always charged to 100% to avoid sufation. With 25 cells I now do exactly 1 mile per AH.

EVcycle
22 June 2011, 1804
Really?

Your definition is no BMS.

Changing the definition now?

Individual charging does not define a Battery management system.

Do you have a controller? Does it have a LVC on it?

That is a component of a BMS....... :)

DRZ400
22 June 2011, 1935
bms is cell level.....pack level hvc & lvc offers no to little protection. single cell chargers are cell level hvc....obviously or you would have used a 3.65 times X charger.

EVcycle
23 June 2011, 0416
So you have you Controller LVC turned off?

DRZ400
23 June 2011, 0633
No, I have it turned on but never hit it....still set at 60v from my agms. I use my CA and monitor the AH's, never using more then 33 of the 40 available. When I charge the CA counts backwards as my charger is on the shunt an not b-. Anyway, you are riding bareback...just not charging bareback. I may put the mini-bms in today, was going to hit six flags but looks like T-storms.

sentinel
23 June 2011, 0720
What Mini BMS it that one?

EVcycle
23 June 2011, 0722
That makes sense.

IMHO, I have yet to see a motorcycle worthy BMS that will survive the road, the weather
or in some cases its own poor design.

We do provide one of the best test beds for all of these electronics.

and please send some of that rain to us. I am tired of mowing our dirt. :)

DaveAK
23 June 2011, 0812
IMHO the MiniBMS is a very worthy motorcycle BMS and quite capable of surving the road, the weather and of course its own design.

teddillard
23 June 2011, 0829
IMHO the MiniBMS is a very worthy motorcycle BMS and quite capable of surving the road, the weather and of course its own design.

Ed, are you saying you don't think the Manzanita is worthy, or did you want to add price as a qualification?

The one thing I see missing is a display that shows all the cells. Am I correct that the CellLog only shows a max of 8? (So you'd need 6 of them, for example, for a 48 cell pack...) Is there anything out there that shows more?

Are the Mini-BMS programmable or settable for other voltages so you could use them for lipo?

Aren't you sad now that I know enough to ask increasingly stupid questions?

DRZ400
23 June 2011, 0926
When you order the mini-bms they can set the voltage thresholds for lifepo4, lipo....I think its an excellent design. Even has temp compensation and protection. I've been using the Signal-lab BMS on my ebike for over 1 year, has at least 100 cycles and works perfectly. 16S4P A123 cells. All cells light up (hit 3.65 v) within 1 minute of each other and off goes the charger. This system could work on a motorcycle but you would have to match the cells as the shunts are only 150ma....but than again thats the same as my Turnigy RC charger which balanced my Calibs several times.

DaveAK
23 June 2011, 0942
Ed, are you saying you don't think the Manzanita is worthy, or did you want to add price as a qualification?

The one thing I see missing is a display that shows all the cells. Am I correct that the CellLog only shows a max of 8? (So you'd need 6 of them, for example, for a 48 cell pack...) Is there anything out there that shows more?

Are the Mini-BMS programmable or settable for other voltages so you could use them for lipo?

Aren't you sad now that I know enough to ask increasingly stupid questions?
Not stupid questions. And all those are features I would like to add to a complete system. The Mini-BMS isn't touted as a complete system though as far as I know, and its price reflects that. For what it is designed for I think it's an admirable product, but you're right in thinking it's no Manzanita.

teddillard
23 June 2011, 0953
I'm not trying to be argumentative with those questions (as it kind of seems, as I re-read). Just trying to get the details straight, understand Ed's comment, etc etc.

I do think, from a balancing standpoint, the Mini-BMS seems like a good value, but I'd want some sort of cell-by-cell level display for all of my cells. The CellLog doesn't do that, does it? Anybody have any resources for something that does?

DaveAK
23 June 2011, 1001
I'm not trying to be argumentative with those questions (as it kind of seems, as I re-read). Just trying to get the details straight, understand Ed's comment, etc etc.

I do think, from a balancing standpoint, the Mini-BMS seems like a good value, but I'd want some sort of cell-by-cell level display for all of my cells. The CellLog doesn't do that, does it? Anybody have any resources for something that does?
I didn't take it as argumentative, more as a reflection of your new love affair. :D

The CellLog does give cell-by-cell level display, but you're right in saying you'd have to have multiples of them as they do a maximum of 8 cells. They're cheap though. And they do also log data if you get the right model.

What I want isn't so much a display of individual cells but a log so that I can see if a particular cell is drifting over time more than the others. Of course, if you're logging data in that kind of detail then a display is a natural addition, but in my mind a secondary function of the real task at hand.

teddillard
23 June 2011, 1023
... more as a reflection of your new love affair. ...

...said the spider to the fly.

(note to self. When I start asking Dave about CAN, run out into oncoming traffic.)

DaveAK
23 June 2011, 1106
...said the spider to the fly.

(note to self. When I start asking Dave about CAN, run out into oncoming traffic.)
Hey, it wasn't any kind of a diss. I think if I was fortunate enough to have a Manzanita to check out I'd be saying the same kind of stuff as you are. It's a beauty, so what's not to love? :D

teddillard
23 June 2011, 1138
Hey, it wasn't any kind of a diss.

Nope, on the contrary, I was referring to how intriguing it is that you're taking this project on. And that it's so far beyond my comprehension, I'd have to call it in, before I'd get something like that done. But that that has never stopped me from immolating (yes, that's the correct word) myself on a project like that in the past. (You can just ask my other buddy Dave. He won't talk to me about anything but beer anymores... after that dicey session with the Hall sensors.)

Why the **** is everybody so ****ing sensitive lately? Jeesh. :eek:

DaveAK
23 June 2011, 1231
Why the **** is everybody so ****ing sensitive lately? Jeesh. :eek:
And what exactly do you mean by this? :mad:

DaveAK
23 June 2011, 1234
.... before I'd get something like that done.
Starting is the easy part. Spending money is also easy. Getting anywhere, well therein lies the problem. :D Mostly down to trying to do too much at once and jumping from one thing to another. This damn day job really gets in the way of progress.

Nuts & Volts
23 June 2011, 1255
Starting is the easy part. Spending money is also easy. Getting anywhere, well therein lies the problem. :D Mostly down to trying to do too much at once and jumping from one thing to another. This damn day job really gets in the way of progress.

Feel ya on this on dave :)

DRZ400
25 June 2011, 1439
My days of riding Bareback are numbered...started installing the Mini-BMS...nice to see all the green lights. I'm not using their head board, just an AC silicon relay mounted to the charger. Probably did ~35 cycles bareback, just got tied of checking the batts during the last 1/2 hour of charge. Even with the adding of the 25th cell the voltages were definately spreading. I had a couple at 3.6 while others were still ~3.45.

DRZ400
26 June 2011, 1723
1370

Let the bms cycle and bleed 3 times....all 24 cells at 3.6v.

billmi
27 June 2011, 1457
Yep. With the small cell size (relatively) the MiniBMS shunts get them balanced quickly.

DRZ400
20 January 2012, 0758
Took the bike out the other day for a quick ride since the temp hit 50F with an overnight low of 33F. I now have 50 cycles on the Minibms which has worked flawlessly. Top speed was down about 7 Mph from the summer....batteries just don't like the cold. I keep my sons 24v sla scooter indoors otherwise he loses at least 50% of his distance.