Sunthing battery 48V 15Ah

[overtonmath]

I just finished reading "Problem with 36v 15Ah not charging"
http://endless-sphere.com/forums/viewtopic.php?f=14&t=53978
About the ordeal with the Sunthing28 battery. I just ordered a 48V 15Ah battery. I ordered it on Sept 17th and it arrived Sept 28th. I was surprised by how fast it came. No duty was required. I was impressed by how it was packaged. Seemed like lots of foam and much protection. I'm still waiting for the motor, so I haven't done anything with the battery or the charger. Should I do something with it now before the motor get's here?

 

[dnmun]

you should charge it first. buy a voltmeter if you don't have one and a watt meter to keep track of the coulombs.

 

[overtonmath]

you should charge it first. buy a voltmeter if you don't have one and a watt meter to keep track of the coulombs.

Do I need a voltmeter and a watt meter if I have it charging through a CA?

 

[dnmun]

i would say you should have one of each. you can use the watt meter to keep track of your battery and the voltmeter is essential to diagnosing the problems when it breaks down.

 

[dogman dan]

For now, put it on the charger using the CA as a volts readout. Confirm that your charger is ok, outputting 58v or so. Confirm that the battery charges fully, after at least overnight on the charger. See if it holds a charge of at least 56v after being taken off the charger.

Once you do get up and running, make those first rides short, followed by overnight charging for a few days. Don't go and run the pack to 100% discharged till you have a few lighter cycles on it.

If you follow all this, and then still find you have some kind of problem with the battery, you will at least know what it's not. Not the charger, Not that the battery never balanced.

 

[overtonmath]

For now, put it on the charger using the CA as a volts readout. Confirm that your charger is ok, outputting 58v or so.

I'm still really new at this. I changed a fuse in my house once and wired some new lighting once, in fact I remember cutting an attached wire before I turned off the power at the fuse box and remember sparks everywhere... I digress.

So, being extra careful, I want to make sure I understand, before I hook anything together. You say put the charger on the CA. The charger has a three pronged plug. Do I need to build a plug to wire connection to connect the charger plug to the CA or can I buy something like that? Do I connect the charger to the CA on the controller side? Which prong on the plug is the positive? Thanks for your help.

 

[dogman dan]

If you don't have the compatible plugs, then don't use the CA on the charger.

I thought you wanted to measure the wattage, watt hours, etc. While charging.

Hook the charger to the charger plug, then you can still monitor voltage of the pack on the output wires. Where presumably you will be putting on a compatible connector.

This is assuming you have the stand alone CA.

 

[overtonmath]

If you don't have the compatible plugs, then don't use the CA on the charger.
I thought you wanted to measure the wattage, watt hours, etc. While charging.
Hook the charger to the charger plug, then you can still monitor voltage of the pack on the output wires. Where presumably you will be putting on a compatible connector.
This is assuming you have the stand alone CA.

Time for pictures. Here is what I have.

Here's my Stand Alone Shunt. I like that they labeled controller/battery sides


Here is the charger with the part that female plug that goes to the battery
View attachment 4

Now here is the Sunthing 48v 15Ah battery with the male plug coming out of it.


Also a female plug that isn't connected to any wires came with the battery. It has letters next to each of the 3 recepticles.
An "N", "E", and an "L" What do those mean? Can I hook the charger to the CA?

 

[999zip999]

Hi just take the voltage of the charger if 58v +. Take voltage of battery if 54 ? volt or about great if a little Less just plug in as it was made to do . Yes ? Lighting in a box. yes it is very alive so be careful...

 

[dogman dan]

Well, I'd say don't mess with anything beyond plugging the charger in to charge the battery, till you have a digital voltmeter.

This is the vital tool that will tell you which wire is + and which is -. It can tell you what voltage the charger puts out, what voltage your battery charged to, and which wire on those plugs do what.

They cost about 10 bucks at harbor freight, unless they are giving them away that day. Or about 15-20 bucks at car parts stores.

Since you will need different plugs for connecting the shunt between the controller and the battery, I would say just get those sorted out. Then you can use the CA to read the voltage of the battery as it charges, using the output wires. Meanwhile get a DVM and use that to see if your battery charged or not.

 

[overtonmath]

I got a DMV and read the instructions. I tested the charger. It tests at 60.4 volts. I started charging it a few hours ago and I noticed that every minute to two minutes it stops charging -- goes to a green and red light. Then maybe 30 sec later it switches back to charging. The green light goes off, the orange light comes on, and it makes that humming sound like its working. Is that normal; stop and start, stop and start? Should I keep charging it like this?

Thanks

 

[overtonmath]

After charging for 3 hours it shut off. Checked the battery voltage, it reads 55.5 v. What should it read? Having read a few other threads, I guess I am suppose to ride this battery around the block for a light discharge and then recharge again. Is that right? I understand that is suppose to help balance the battery but could someone explain what is actually happening to the individual batteries inside the battery brick? Thank you

 

[overtonmath]

I would like to hook my battery to the bike and discharge it a little, but I can't figure out what to plug into the battery. I think I need to build a female plug to plug into the battery and then those Anderson 45 amp power poles to connect to the shunt/controller.
btw. I picked up my motor today. Just trying to figure out how to connect the battery to the motor. Thanks.

Sunthing 48v 15Ah battery with the male plug coming out of it.
View attachment 3

 

[overtonmath]

After charging for 3 hours it shut off. Checked the battery voltage, it reads 55.5 v. What should it read? Having read a few other threads, I guess I am suppose to ride this battery around the block for a light discharge and then recharge again. Is that right? I understand that is suppose to help balance the battery but could someone explain what is actually happening to the individual batteries inside the battery brick? Thank you

Battery had been off the charger for a few hours and I checked he voltage again. It had dropped to 54.1v. I wondered if that was the cells balancing themselves. Anyway I hooked back up to the charger and charged for an hour the charger kept going off then back on then off and so forth. Just disconnected the charger and the battery now measures 56.1v. Haven't used with the motor yet.

 

[dogman dan]

That on off cycle is the bms working to balance the pack. Put it back on the charger, and keep on charging. It looks like nothing is happening, but when the green light is on, it's discharging the highest cells.

Since you have 55v, it's not done, some cells are still low. Once you get the bike up and running, keep your rides very short for at least 3-6 charges. Keep charging 24-7, till the bike recharges to 60v quicker. Then you will know you are balanced, when you see 58-60v (when unplugged from the charger) when the charger goes green.

Once you have it fully charged, it might hold all 60v overnight. It wont do that for all that long though, and normal is for the voltage to drop to 56-58v overnight. In time, possibly pretty soon, you won't see all 60v when you unplug. 2v may vanish the instant you unplug. It's called surface charge. But 55v is definitely not ideal, hopefully you see at least 56v when it's new and fully charged.

Then when you start riding, expect to see about 54v very soon, and most of your ride will be between 52 and 54v. The usable meat of the charge is below 3.5v per cell. The rest above 56v, is the overcharge that is not harmful to lifepo4, but helps the charger and bms balance the pack quicker.

You will need to put plugs on the discharge wires. My preference is Anderson 45 amps powerpoles. Others prefer 4mm bullet connectors from a hobby store. You will need two sets. One set between battery and shunt, the other between shunt and controller.

Till you get those connectors, you can use household wiring wire nuts to temporarily connect.

 

[overtonmath]

You will need to put plugs on the discharge wires. My preference is Anderson 45 amps powerpoles. Others prefer 4mm bullet connectors from a hobby store. You will need two sets. One set between battery and shunt, the other between shunt and controller.

Till you get those connectors, you can use household wiring wire nuts to temporarily connect.

Ok I understand those suggestions, but what about the connection to the battery. The battery has a male 3 pronged plug that looks alot like a plug from the power supply on a computer. What I need to build, I think, is a female plug that connects to the battery (see picture above) and the anderson 45 amp power poles on the other end.

My question is how do I build that female plug. Which side should be positive (red)? What is the middle wire? The female plug that came with the battery has strange letters on the different holes. "N", "E", and "L" Does anyone know what these stand for? If I wire the female plug wrong will I blowup my battery?

Thanks

 

[dogman dan]

You saying the male plug going to the charger is the ONLY wire?

Nearly all bms have one plug (or set of wires) to input charging, and another to output discharging. If you have no bms, then you have one plug. Sometimes they share a common negative wire. The way your charger was acting, I think you must have a bms though.


Those computer plugs make a so so connector to the controller. In general, you'd prefer a fatter wire than they use in any AC computer plug and wire. But you could go to a thrift store, and get one for a buck or two.

Red is + on your shunt, black is -. On your battery plug, use the voltmeter to determine which is + and which is -. You won't need the middle ground wire connecting to the controller.

Reviewing, you have a plug with three prongs. It's possible that plug has one negative, and two positives. One positive for charging, one for discharging. Your voltmeter would show that if that is the case.

I doubt it's that way though, Sure you don't have two more wires on the pack someplace, hidden under some tape maybe?

 

[overtonmath]

You saying the male plug going to the charger is the ONLY wire?

Nearly all bms have one plug (or set of wires) to input charging, and another to output discharging. If you have no bms, then you hav
e one plug. Sometimes they share a common negative wire. The way your charger was acting, I think you must have a bms though.

Sure you don't have two more wires on the pack someplace, hidden under some tape maybe?

I took the batter off the charger and really inspected it. There are no more plugs other than the one I showed in the picture above. There is a blue wire and a red wire going into that male plug that's on the battery.

Red is + on your shunt, black is -. On your battery plug, use the voltmeter to determine which is + and which is -. You won't need the middle ground wire connecting to the controller.

Reviewing, you have a plug with three prongs. It's possible that plug has one negative, and two positives. One positive for charging, one for discharging. Your voltmeter would show that if that is the case.

How do I use the voltmeter to determine which is positive and negative and if there are two positives on the battery plug?

Check out the pictures on this ebay listing. This is the battery I have. It states that it has a BMS and shows the battery wiring
http://www.ebay.com/itm/2013-48v-15...US_Rechargeable_Batteries&hash=item20d7106708

 

[dogman dan]

Thinking it through, if there is only two wires to that plug, then you can't have a second positive. That would require a third wire.

This is a new one for me, all my bms equipped packs have had a separate charge plug, and I had been informed that Sunthing used a similar bms to the pings I had. Ask Sunthing is the next step I suppose. Apparently your charge plug is also your discharge plug.

Likely the two outside prongs connect to those two wires, and the third is just not connected to anything.

Your voltmeter should have the red wire on it plugged into V and the black plugged into COM. When set up that way, putting the red wire of the voltmeter on a + prong of the plug and the black on the other will result in a positive readout. If it's a negative voltage, then you have the red wire on the negative.

 

[overtonmath]

Ask Sunthing is the next step I suppose. Apparently your charge plug is also your discharge plug.

I emailed Sun-thing. here was our exchange:

Dear sun-thing28,

All batteries that I have seen before have separate charge and discharge wires. Does your battery have separate charge and discharge wires??
Thanks

hi friend

our battery is the charge and dischange use the same plug.

if you really want to separate it , we can do it for you.

what do you think?

hi friend

you can see the spec of bms on the ebay page.

Charging cut-off voltage: 58.5V

Discharge cut-off voltage: ≤ 45V

Nominal discharge current: 20A

Instantaneous maximum discharge current: 30A

Rated charging current: 5A

Maximum charge current: 8A

Dear sun-thing28,

I saw those specifications already on your website. What my question is, is what is the model and maker of the bms?

thank you for your help.

hi friend

the maker is HTL.

 

[dogman dan]

I began to wonder if there was still a bms. So now you need to just find a computer plug to hook your shunt to.

You aren't running huge power, so one from the thrift store should work ok, but it will be thin wire, so make it as short as possible, and use thicker wire for the rest of the run to the controller if it's longer than a few more inches.

Or, what I would do is chop that computer plug off, and replace it all with 12g wire and 45 amp andersons. But, the chance is good that in the process I'd wire it backwards, plug in the charger and smoke it. Even with all my experience, I can still get dumb enough, in a hurry enough to do it again.

 

[overtonmath]

But, the chance is good that in the process I'd wire it backwards, plug in the charger and smoke it. Even with all my experience, I can still get dumb enough, in a hurry enough to do it again.

Ok. so I need to make sure its wired correctly because I could permanently mess up the battery. That's good to know. I also figured out which was positive and negative using that volt meter you told me about. With negative volts indicating that the red "stick" is on the black. I was impressed by that. Thanks.

I have to buy and rewire the 6 circuit wire connector coming of the motor. I needed an extra washer and couldn't get it over that connector, so I had to cut it off. I'm now looking for a new connector to buy and rewire those wires.

Do I need a special tool to crimp the wire on to the connector pieces?

The noob saga continues.

 

[dogman dan]

Here's the affordable crimper I am using. You should practice some with cheap connectors before trying it on something you don't have many of, or something that costs a lot.

http://www.electricbike.com/crimp-anderson/

 

[dnmun]

why did you cut the charging plug off? the extra plug he sent you is so you can connect it to the controller or you can hard wire it.

 

[overtonmath]

why did you cut the charging plug off? the extra plug he sent you is so you can connect it to the controller or you can hard wire it.

I'm sorry, I wan't very clear. It was a 6 circuit plug that I cut off the wire coming out of the EM3 motor. I needed to put on another washer and it wouldn't fit over the clip.

So the sunthing battery has been on the charger 24/7 for two days and still only registers at 56.4 V. I haven't got the bike up an running yet, so I've left it on the charger. Should I keep the battery on the charger still after two days?

Thanks.