beef_wellington
1 W
I'm not really sure what caused the fuses to pop. I don't have a multimeter, so I couldn't test anything. This morning everything was fine again, and the commute was smooth sailing.
Time to build... and ask dumb questions
- Thread starter beef_wellington
- Start date
beef_wellington
1 W
Ok. Another NiCad question. These batteries do get warm after discharge, which I hear is normal. If I plug them into the chargers right away, the charger flashes red/green telling me that they are above the temperature threshold of the sensor (thermistor?). So I have been waiting for them to cool before plugging them in. I assume this is the best thing to do as mentioned previously for the first charge. If I plug them in hot, would the charger just kick in when they cool? Or should I avoid doing this entirely?
Let them cool down completely before you plug them in if you can. ( best practice )
Once the temp cools down just enough to allow the charget to charge.. the pack is still pretty warm and this can cause an incomplete charge.
Once the temp cools down just enough to allow the charget to charge.. the pack is still pretty warm and this can cause an incomplete charge.
dnmun
1 PW
nicads actually cool off during charging, maybe nimh will get hotter, but giving them some rest is likely best.
the intelligent chargers use the negative dV/dt signal from the nicads when they reach an overcharged state to terminate the charge. when the charge voltage climbs to about 1.41V/cell then the cell is 100% charged and should not be overcharged because it just creates more hydrogen gas inside the cell which puts pressure on the seals, and when they go too far then the cell vents and loses fluid which eventually is how the nicads end up dead, from venting during overcharge.
the charger can detect the DROP in voltage as the cell is charged beyond 1.41V and it then shuts off charging totally. you should not leave nicads or even nimh on a trickle charge. turn the charger off, do not let it trickle charge, and repeated the 3rd time, turn the charger off and do not allow it to trickle charge, that will double the life expectancy of the nicads.
the voltage drop for nimh is similar, but the change in voltage is so much smaller that it is harder for the charger to detect, so nicads are charged using a nimh charger also since they both need to charge to the same 1.41V endpoint and use the same termination signal.
richard said that he had a 12 year old nicad which he pulled out of storage and it charged up and worked fine. you are supposed to leave them at 40% charge when put into storage, not 100%. also the nickle hydroxide filaments grow in size if the battery is not regularly discharged down to very low levels. i saw one paper where an automatic discharge circuit discharged the cells down to .4V to dissolve the filaments and keep them small enough that they did not grow so large that they damaged the separator, which is the biggest problem with aging nicads. you have to keep the current very low during this discharge to prevent damage, but the cell will come back with even more storage capacity. in fact this is how you 'recondition' old nicads with no capacity left because of the 'memory' problem. regular discharge to these low levels is supposed to prevent the aging effects from reducing their capacity.
i have a couple of justin's nicad packs too, 5Ah and 4.5Ah 48V, bot used off the selling page here, with the little nexcel 3A charger, $215 delivered. BOL, dennis
the intelligent chargers use the negative dV/dt signal from the nicads when they reach an overcharged state to terminate the charge. when the charge voltage climbs to about 1.41V/cell then the cell is 100% charged and should not be overcharged because it just creates more hydrogen gas inside the cell which puts pressure on the seals, and when they go too far then the cell vents and loses fluid which eventually is how the nicads end up dead, from venting during overcharge.
the charger can detect the DROP in voltage as the cell is charged beyond 1.41V and it then shuts off charging totally. you should not leave nicads or even nimh on a trickle charge. turn the charger off, do not let it trickle charge, and repeated the 3rd time, turn the charger off and do not allow it to trickle charge, that will double the life expectancy of the nicads.
the voltage drop for nimh is similar, but the change in voltage is so much smaller that it is harder for the charger to detect, so nicads are charged using a nimh charger also since they both need to charge to the same 1.41V endpoint and use the same termination signal.
richard said that he had a 12 year old nicad which he pulled out of storage and it charged up and worked fine. you are supposed to leave them at 40% charge when put into storage, not 100%. also the nickle hydroxide filaments grow in size if the battery is not regularly discharged down to very low levels. i saw one paper where an automatic discharge circuit discharged the cells down to .4V to dissolve the filaments and keep them small enough that they did not grow so large that they damaged the separator, which is the biggest problem with aging nicads. you have to keep the current very low during this discharge to prevent damage, but the cell will come back with even more storage capacity. in fact this is how you 'recondition' old nicads with no capacity left because of the 'memory' problem. regular discharge to these low levels is supposed to prevent the aging effects from reducing their capacity.
i have a couple of justin's nicad packs too, 5Ah and 4.5Ah 48V, bot used off the selling page here, with the little nexcel 3A charger, $215 delivered. BOL, dennis
beef_wellington
1 W
Thanks Y and Dennis.
I woke up this morning and plugged the packs in, and got a temperature sensor error again on both packs (?). They were totally cool. I have no idea what's happening, after two successful charges so far. I'm going to get a multimeter so I can at least see what the packs have in them.
I woke up this morning and plugged the packs in, and got a temperature sensor error again on both packs (?). They were totally cool. I have no idea what's happening, after two successful charges so far. I'm going to get a multimeter so I can at least see what the packs have in them.
Popping fuses randomly, unable to charge... something is definitely wrong somewhere. :? Best of luck tracking it down... let us know what you find out.
Are you seperating the packs from 72v to 36v before you plug in the chargers ? Or leaving the packs in series and hooking up both chargers ? ( You have to seperate them if they use common ground.. i don't fully understand this concept yet, but i do know the HIPower chargers are not isolated )
You should NOT be popping fuses.. what Amp rating are you using ? ( or the color of it )
You should NOT be popping fuses.. what Amp rating are you using ? ( or the color of it )
beef_wellington
1 W
Yes I am disconnecting the packs from the controller and each other prior to charging. I pulled out the original fuses that had a little 25 on them, and replaced them with ATC-25 auto fuses from Walmart. Only ones I saw that had a 25 on them. They have a clear plastic casing on them.
I took another short run as I knew the batteries were still half charged, picked up a multimeter. Both packs are showing between 37-38V.
I went to check the chargers and got nothing from pin 1 (as pos) and pin 2 (as neg). However I am getting a read of 4.7 when putting the positive in pin 3 (temp sensor) with the negative in either port 1 or 2. I don't know what I am supposed to be seeing, but I would assume that I should see a voltage through pins 1 and 2. This being +/- as indicated in the spec sheet that came with the chargers. And I already got two full charges from these already. I am confused. Any ideas?
I took another short run as I knew the batteries were still half charged, picked up a multimeter. Both packs are showing between 37-38V.
I went to check the chargers and got nothing from pin 1 (as pos) and pin 2 (as neg). However I am getting a read of 4.7 when putting the positive in pin 3 (temp sensor) with the negative in either port 1 or 2. I don't know what I am supposed to be seeing, but I would assume that I should see a voltage through pins 1 and 2. This being +/- as indicated in the spec sheet that came with the chargers. And I already got two full charges from these already. I am confused. Any ideas?
dnmun
1 PW
i'm not familiar with the circuit, but if you have temperature sensor, it is a thermistor which has a voltage drop that signals when the charger should be sending current. as the pack gets too hot, then the thermistor voltage drops and that would shut off the charge circuit. so if you see no voltage on the plug, it may be cause the thermistor is not making the complete circuit back to the charger and so the charger will not send current to the plug. if this is from ebikes.ca, justin or zev will know. i have no temp sensor on my packs.
beef_wellington
1 W
Another thing that I forgot, which could be (most likely is) the entire problem, is the male-to-male XLR adapters that I got. I noticed today that when the chargers are plugged in (to the wall, not the batteries), and I touch the adapters with my hand, the charger light flashes red/green (temp sensor error). I neglected to mention this in the previous post. My guess is that these adapters are somehow tripping the sensors. I'll get some more at the local music store tomorrow, as they probably have better quality adapters than the electronic wholesale shop.
If that doesn't work, I will refer the ebikes.ca folks to this post for their input.
If that doesn't work, I will refer the ebikes.ca folks to this post for their input.
dnmun
1 PW
do you mean that the plugs are loose in their connection? and then the thermistor signal is intermittent as you wiggle the plug? how did you end up with the plugs having the wrong sex? does justin know this is a problem? they usually have that stuff covered, but you were able to charge the pack up once already as i remember. the thermistor lead will likely be the middle one, maybe the springs are mashed open and not making contact with the pin.
beef_wellington
1 W
I mean my skin touching the adapters tripped the thermistors. The chargers were bought from batteryspace.com as recommended by Alison. Renaissance didn't have any 36V chargers in stock when I ordered. I verified that the pin charges and specs matched up prior to ordering. I didn't realize the sexes wouldn't match until I got the chargers in the mail, then I went out and bought the adapters. The adapters seem to work just fine, without an intermittent connection, at least with the first couple of charges. They do feel a little bit loose as the XLRs don't fully lock into place. I will post an update when I get new male-to-male adapters in the morning.
beef_wellington
1 W
I wasn't able to find adapters that were different than the ones I already have, so I soldered male XLR connectors on the battery packs to avoid using the male-to-male adapters. This solved the charging problem. Not sure about the fuses popping. Hopefully that problem is gone.
beef_wellington
1 W
Update:
No more popping fuses and everything seems to be working just fine. My only issue now is that the batteries don't seem to have as much power as the first few charges. I'm not sure if this is typical, or if they are "settling in" or something like that. My riding habits are to pedal and shift through the gears, while supplementing with a moderate amount of throttle. Once I get to where my feet can not move any faster, I give some more throttle and have plenty of room for speed on top of that. For the past 4-5 charges it seems as though I have little acceleration above my top gear, and my overall unassisted top speed is lower. I do not have a Cycle Analyst (yet), which I am sure would make troubleshooting things like this much easier.
Possible reasons for this...
Bad soldering? - This was my first attempt at soldering, and I thought I did a fairly decent job. Male XLR charge connectors on each battery pack. Maybe one of the connections wasn't 100% and is preventing a full charge (although my multimeter is showing >72V)?
The other solder job was on the Andersons that made up for the gap between my motor cable and the controller cable. All I could find was Anderon connectors with 10 gauge wires (the controller cables seem a bit smaller). I cut the wires and stripped the rubber back about 1/4". Then I frayed out the strands so the two wires could be pushed into each other. I gently twisted it together and gave it a coat all the way around with electrical solder. Then I put heat shrink and electrical tape around each of the three cables, followed by some heat shrink over the three as a single connector. It seems like a good connection to me, but I know nothing about soldering.
Maybe I broke one of the cardinal sins of soldering, and someone can fill me in.
Charging Habits? - I thought someone mentioned to not trickle NiCads, and to remove them from the charger once complete. I emailed Justin about this, and he said that it is not really an issue to worry about (NiMh are a different story). Plus the chargers that I have should terminate entirely upon achieving a full charge. Before I got this info, I had purchased a Christmas light timer that would terminate after 6 hours. So the batteries sat plugged into the unpowered chargers for a few hours once the timer went off. I have run down the batteries once to where I could notice a big difference in power and speed, so I know they have been through at least one good deep charge.
Maybe I just need to order that CA to know what is really happening, but if anyone can shed some light it would be much appreciated.
No more popping fuses and everything seems to be working just fine. My only issue now is that the batteries don't seem to have as much power as the first few charges. I'm not sure if this is typical, or if they are "settling in" or something like that. My riding habits are to pedal and shift through the gears, while supplementing with a moderate amount of throttle. Once I get to where my feet can not move any faster, I give some more throttle and have plenty of room for speed on top of that. For the past 4-5 charges it seems as though I have little acceleration above my top gear, and my overall unassisted top speed is lower. I do not have a Cycle Analyst (yet), which I am sure would make troubleshooting things like this much easier.
Possible reasons for this...
Bad soldering? - This was my first attempt at soldering, and I thought I did a fairly decent job. Male XLR charge connectors on each battery pack. Maybe one of the connections wasn't 100% and is preventing a full charge (although my multimeter is showing >72V)?
The other solder job was on the Andersons that made up for the gap between my motor cable and the controller cable. All I could find was Anderon connectors with 10 gauge wires (the controller cables seem a bit smaller). I cut the wires and stripped the rubber back about 1/4". Then I frayed out the strands so the two wires could be pushed into each other. I gently twisted it together and gave it a coat all the way around with electrical solder. Then I put heat shrink and electrical tape around each of the three cables, followed by some heat shrink over the three as a single connector. It seems like a good connection to me, but I know nothing about soldering.
Maybe I broke one of the cardinal sins of soldering, and someone can fill me in.
Charging Habits? - I thought someone mentioned to not trickle NiCads, and to remove them from the charger once complete. I emailed Justin about this, and he said that it is not really an issue to worry about (NiMh are a different story). Plus the chargers that I have should terminate entirely upon achieving a full charge. Before I got this info, I had purchased a Christmas light timer that would terminate after 6 hours. So the batteries sat plugged into the unpowered chargers for a few hours once the timer went off. I have run down the batteries once to where I could notice a big difference in power and speed, so I know they have been through at least one good deep charge.
Maybe I just need to order that CA to know what is really happening, but if anyone can shed some light it would be much appreciated.
docnjoj
1 GW
Nicads need a few cycles to break in! Also the charger seems to be "smart", so it trickles on its own. Nicads are self equalizizng with extended trickle charge. Let em' cook overnite!
otherdoc
Afully charged Nicad 36 volt pack should register around 1.4 volts per cell or 42 volts!
otherdoc
Afully charged Nicad 36 volt pack should register around 1.4 volts per cell or 42 volts!
beef_wellington
1 W
thanks doc. I'll "cook" them for a couple of charges and report back.
beef_wellington
1 W
Two and a half years since my build and I'm back... trying to re-educate myself on how to get charged up and back in the saddle.
Originally, I spent a few months riding my ebike around and commuting to work, having a wonderful time. The chargers that I originally bought from batteryspace were crap, and eventually screwed up my packs. Had cell reversals, nothing held a charge more than a couple miles. I ordered replacement cells from Justin, and made a couple of attempts at troubleshooting, finding and replacing the bad cells. Living in a studio apartment, and using half of my living space as a bicycle lab got old very fast. Sad to say, I gave up.
Now I bought a house and have the space and desire to rebuild. I will see if my original packs from Justin can be salvaged, and buy one from Ping, if not. I was just reading through my old posts and wanted to give a little update. I'm quite happy to see the same great people here helping this movement.
Originally, I spent a few months riding my ebike around and commuting to work, having a wonderful time. The chargers that I originally bought from batteryspace were crap, and eventually screwed up my packs. Had cell reversals, nothing held a charge more than a couple miles. I ordered replacement cells from Justin, and made a couple of attempts at troubleshooting, finding and replacing the bad cells. Living in a studio apartment, and using half of my living space as a bicycle lab got old very fast. Sad to say, I gave up.
Now I bought a house and have the space and desire to rebuild. I will see if my original packs from Justin can be salvaged, and buy one from Ping, if not. I was just reading through my old posts and wanted to give a little update. I'm quite happy to see the same great people here helping this movement.
Good to see the update! Sad to hear of such problems. 
If we can help, don't hesitate to ask, ya know.
If we can help, don't hesitate to ask, ya know. beef_wellington
1 W
Hi Amberwolf.
Well since you offered... I am trying to get caught up on the latest in the world-of-batteries since my last attempt. It is my understanding that many are building from hobbyking packs, which requires a moderate amount of knowledge/effort in charging, balancing, building, etc... maybe a little too ambitious for me at the moment.
If my old pack cannot be salvaged...I am considering buying a Ping pack, due to his reputation here and plug-n-play setup. I'm also trying to find out more about cell_man's packs, and what the differences/benefits might be to getting one of those. I would prefer to attempt an in-frame mounting method, for which a cell_man pack may be better suited.
Not too versed on pros/cons on an A123 pack vs. LiFePO4.
The amount of power and speed I got from the 72V of NiCads was perfect before their demise. I am hoping to get similar performance from my new purchase, with more range than my previous 8ah. Just want something that will get my 200lb. frame upwards of 30 mph.
I have a 25A pedal first controller from ebikes.ca. Not sure is that can be used with a new pack.
I haven't exactly posed any questions here, but any informed input is much appreciated. Thanks.
Well since you offered... I am trying to get caught up on the latest in the world-of-batteries since my last attempt. It is my understanding that many are building from hobbyking packs, which requires a moderate amount of knowledge/effort in charging, balancing, building, etc... maybe a little too ambitious for me at the moment.
If my old pack cannot be salvaged...I am considering buying a Ping pack, due to his reputation here and plug-n-play setup. I'm also trying to find out more about cell_man's packs, and what the differences/benefits might be to getting one of those. I would prefer to attempt an in-frame mounting method, for which a cell_man pack may be better suited.
Not too versed on pros/cons on an A123 pack vs. LiFePO4.
The amount of power and speed I got from the 72V of NiCads was perfect before their demise. I am hoping to get similar performance from my new purchase, with more range than my previous 8ah. Just want something that will get my 200lb. frame upwards of 30 mph.
I have a 25A pedal first controller from ebikes.ca. Not sure is that can be used with a new pack.
I haven't exactly posed any questions here, but any informed input is much appreciated. Thanks.
From what I've read, it could be a bit daunting, but there are some good LiPo threads that give all the basic info and even some good component recommendations. I have no experience with it yet; still getting my feet wet with a rebuilt/repaired Vpower LiFePO4 pack.beef_wellington said:
A123 *is* LiFePO4, just a slightly different flavor--typically it has higher discharge (and charge) ratings than the usual stuff, and longer lifespan. Again, no direct experience yet.
I do have some Thundersky 60Ah LiFePO4 cells I have experimented a bit with, but only 10 of them (32V), so no "performance" tests yet.
Gotta wait till I have my middrive setup working again to use them for anything approaching normal speeds (the hubs I have won't run very fast on that voltage, probably significantly < 15MPH). But these cells are huge and kinda heavy, and only really 1-2C...of course, 1-2C at 60Ah is 60-120A. I don't typically hit even 8-9A continuously with the 9C hub for 20MPH, so it isn't a big deal to me. A bit over 60A peaks at startup, not even long enough to see on the display before it drops to 30-40A and then rapidly down from there. The A123 or the HK LiPo would do what you're after, I think. Cell-man would be the easiest way to get prebuilt A123 packs, which AFAIK would also be *new* cells, rather than you having to find and test and rebuild used toolpack cells into your ebike pack.
[/quote]
If it's the same voltage range, then sure it could. Even less would be ok if the controller doesnt' have an LVC or if the LVC is low enough to not cut off early vs your pack's voltage.
BTW, if you decide to replace the NiCd pack and not keep it, it would be nice if you put it up on ES for sale; I'm sure someone would like to rebuild it into something usable for their own bike. (I've done this with NiMH from two people, and the Vpower from another; without taht I couldn't have afforded to move up from SLA, really--certainly not the way I have, or for multiple bikes). Someone else could definitely use a break like that, too.
(I don't currently have any free budget or I'd be interested).beef_wellington
1 W
Thanks for the info.
Before I purchase anything, I am going to dust off the NiCad packs and see if I can fix them. If not, I'll find them a new home with someone here on the forums. Until then I'll be reading (and re-reading) all these battery posts to make some sense of it all.
Before I purchase anything, I am going to dust off the NiCad packs and see if I can fix them. If not, I'll find them a new home with someone here on the forums. Until then I'll be reading (and re-reading) all these battery posts to make some sense of it all.
