Easy question about XB-600 full charge.

Anything over 56-57V would be bad. The problem with charging and the xb600 and other bikes with series packs is this..... IF/WHEN only one of the batteries in the pack goes bad or gets drained more than the others, this is when the real risk of overcharging and meltdown occurs. a normal 12V battery is normally fully charged between 13.5 and 14.2V and most will level off down to about the 13.5V within an hour after charging is complete. The problem with a battery PACK is this... If 1 battery starts charging at say 12V while the other 3 start at 13V this is what happens... say a full charge and anything over this would damage the battery is 14V for this example.... By the time the "pack" reaches the 57V shutoff voltage for the charger, assuming an evenly distributed across each battery you end up with this..... 1 battery at 13.5 and 3 batteries at 14.5 for a full pack voltage of 57V!!!! The problem is the 3 batteries at 14.5V would be damaged from the overcharge thus go bad and make the pack voltage drop down (due to the damaged batteries no longer being able to hold even a 14V charge properly) and eventually ruin that last battery if the charger is left on long enough.

Because of this problem there are only a few ways to be "sure" and even less to be absolutely sure.... Install 3 battery maintainers in your 4 battery pack to keep them perfectly balanced. Modify the pack to charge them in parallel to maintain near perfect balance. And/or use a timer to shut off the charger after a pre-determined time interval... IE if you had a fully charged pack and only drove it say... 5 miles, that should require no more than a couple of hours charge at the most. I am not sure how to do it, but you CAN install thermometers near the batteries in conjunction with a relay to disconnect the flow from the charger at a certain temperature.

So for a short answer... a 48V stock pack on the xb-600 should read no more than 57V WHILE CHARGING. And should level off to about 54V within an hour or so after charge is complete.

Buzzer,
Your question is easy, it's the answer that is a little harder.
The XB charger output is right around 58 volts, and you will see a drop from this when first connected to the pack and charging starts.
On a good pack the voltage will come up as current goes down during the charge cycle. Having not measured the voltage against current during a charge cycle I can't tell you or plot a curve as to when the charger considers the pack full and goes to float mode.

I suspect that most of the thermal meltdowns are due to battery issues rather then a charger malfunction. I just had that meltdown joy this week.
Without the charger taking into account the pack temperature, when one or more batteries can not be brought to full charge the current never drops low enough for the charger to enter float mode. Now all the batteries are being cooked. The full ones are over charging creating heat, and the ones that cant take a full charge can no longer convert the electricity to chemical storage, so they overheat The charger is happy to try and bring up the batteries that wont accept a full charge and the next thing you know the 4 batteries have fused into 1 big block of plastic and lead.

The whole time the charger never went over voltage or current on the pack. That is why you hear about temperature compensating chargers. With the chargers we have the only real defense is a time cutoff and to check the individual batteries voltage.

Some have changed the wiring to allow charging the batteries individually. If you search the forum for "anderson powerpole" you will find some info on changing over to individual charging. The draw back with this is you need 4 chargers or can only charge 1 battery at a time.

I am working on a project to have a temperature cutoff for the charger so that I don't fry my new batteries. The problem I am running into is that here in Southwest New Mexico the outside temp in the summer is very close to the cutoff point I want of 105F degrees. When I have a solution I will post it.

BTW my pack was 25 months old, charged every day. My range was down to about 8 miles and the pack had a total of 4196 miles on it. I replaced the batteries with 22Ah ones and will write a review when I have some miles on them.

Some have changed the wiring to allow charging the batteries individually. If you search the forum for "anderson powerpole" you will find some info on changing over to individual charging. The draw back with this is you need 4 chargers or can only charge 1 battery at a time.

BTW my pack was 25 months old, charged every day. My range was down to about 8 miles and the pack had a total of 4196 miles on it. I replaced the batteries with 22Ah ones and will write a review when I have some miles on them.

Actually, with the Anderson Powerpole method, the pack is essentially re-wired into parallel mode instead of series. This allows you to charge ALL 4 batteries at once with a single 12V charger, such as the one I got from Walmart for about $25. This charger allows you to charge at 6 or 12V and at 2,4, or 6 amps. At 6 amps that is equal to 1.5 amps per battery which is perfectly acceptable.

As far as your batteries go.... what brand did u get??? I just bought 5x 12V 22ah Universal batteries model UB12220 had them for about a week now, seem just as good as the original stock batteries.

Actually, with the Anderson Powerpole method, the pack is essentially re-wired into parallel mode instead of series. This allows you to charge ALL 4 batteries at once with a single 12V charger, such as the one I got from Walmart for about $25. This charger allows you to charge at 6 or 12V and at 2,4, or 6 amps. At 6 amps that is equal to 1.5 amps per battery which is perfectly acceptable.

I don't really like charging in parallel with only one charger, I know it is a common practice. Once again a battery lower then the rest can be an issue. Your assumption of 1.5A per battery is only when all batteries are at the same state of charge. You could very well dump all 6 amps into one battery until all batteries are at equal charge. At 6amps this may not be a problem for your batteries. Use of a larger charger might allow the charge current to exceed the maximum of an individual battery until equalized.

A search on parallel charging shows a mix of opinions and ways to connect the charger. Some say + to fist battery and - to last battery when connecting the charger. Some do it, some don't do it, again opinions. In case you don't have one you are welcome to mine.

I replaced my batteries with Tempest TD22-12's which claim to be a "true deep cycle" battery. I'll have to let you know if they stand up to the claim.

Actually, with the Anderson Powerpole method, the pack is essentially re-wired into parallel mode instead of series. This allows you to charge ALL 4 batteries at once with a single 12V charger, such as the one I got from Walmart for about $25. This charger allows you to charge at 6 or 12V and at 2,4, or 6 amps. At 6 amps that is equal to 1.5 amps per battery which is perfectly acceptable.

I don't really like charging in parallel with only one charger, I know it is a common practice. Once again a battery lower then the rest can be an issue. Your assumption of 1.5A per battery is only when all batteries are at the same state of charge. You could very well dump all 6 amps into one battery until all batteries are at equal charge. At 6amps this may not be a problem for your batteries. Use of a larger charger might allow the charge current to exceed the maximum of an individual battery until equalized.

A search on parallel charging shows a mix of opinions and ways to connect the charger. Some say + to fist battery and - to last battery when connecting the charger. Some do it, some don't do it, again opinions. In case you don't have one you are welcome to mine.

I replaced my batteries with Tempest TD22-12's which claim to be a "true deep cycle" battery. I'll have to let you know if they stand up to the claim.

you DONT have to charge at 6 amps.. .the slower u charge the better!!!! And u are wrong!!!! once a "pack" is wired in parallel all batteries will auto equalize. unless 1 is bad... in which case the others will STILL cause a voltage high enough to cut off the charger before a meltdown occurs!!!! It is virtually impossible to overcharge a pack in parallel!!!!!! If you are THAT worried charge it at 2 amps and 12V, a slower charge is all the better!!!! at 12V and 2 amps there is pretty much NO i repeat NO possible way to fry you battery pack overnight in less than 8 hours !!!!!!!!!!!!!!!!!

The amperage is too low to cause a severe overcharge unless you let it go for 24+ hours !!!!!

Once again.... Unless i am severely mistaken (dont think i am) if you connect a set of batteries in parallel, they will ALL settle to an even voltage... IE if 2 are at 14 and 2 are at 12.... they will ALL go to 13V even if you DONT supply a charger to them. Even if you DO.... the other 3 batteries (in the event of 1 fails!!!!) will STILL reach the proper charging voltage and SHUT OFF THE CHARGER !!!!!!!!!!!!!!!!!!!

I appreciate your input james... but unless i am VERY wrong and i dont think i am... by the laws and properties of circuit dynamics.... that a pack of batteries in parallel WILL even out by those laws. I have even done it in person............ I had 1 battery at 12V and the other 4 at 13V... wired them in parallel..... in 10 minutes they were ALL at about 12.6V !!!!!!!!!!!!!

In parallel the charger will "SEE" the highest battery's voltage reguardless of the other batteries, such if ANY battery reaches the shutoff voltage it WILL shut off and go to a float charge !!!!! This is the MAJOR advantage of charging in parallel!!! like i said it is almost impossible to overcharge a pack. I DID say almost!!!! But the chances are VERY rare and a LOT less than if u charge in series !!!!!!!!!!!1

After reading this I was thinking that charging in parallel makes alot of sense. Could you just install 3 SPDT relays between the series battery connections to break the connection. Also you would wire all the batteries in parallel and attach the two leads to a charger after you activated the SPDT relays and broke the series connections. I hope I am explaining my idea corerectly.

DPDT relays COULD be used to make the change from series to parrallel, but keep in mind, they would need contacts rated to carry the worst-case amperage of accelleration/hillclimbing, making for pricy/large relays and wiring. When charging lead-acid batteries in parallel, normally no problem arises, except in the event one or more batteries has a shorted cell, causing it to draw all the others down, and overheat itself-no loss, as it is already bad anyhow! Start with all batteries/cells identical, new, same age, brand/type, and replace them ALL when failure occurs! Mixing different types/brands/ages is most harmful to balance!--Bob

It probably has something to do with that Ohm's Law thing of Voltage=Amperage multiplied by resistance. If the resistnce is the constant in the formula, lower volts means higher amperage. a pack of 12v/20Ah batteries in parralel would make for a 12v/80Ah pack. Advantage, you could use all the automotive accessories you wanted with no converter. Now, if a 12Volt motor could produce the kinds of rpms to propel the bike, and the resistance stays the same in the circuit, the amperage, (and thus the wattage) goes up. A 12V motor trying to work as much as a 48V motor with the same resistance would be... (48/12=4 x 500(watts)= 2000Watt rating (watts = Amps * Volts, in DC circuits) This is assuming a lot on the formulas, for instance DC motors only, AC is another story) And somewhere back in all this mess it goes back to horsepower too! :-) If this makes sense, you've been reading way too many forums :-) .

The batteries are in SERIES because using a higher voltage motor is more practical/economic. A lower voltage, such as 12 volts, would require FOUR TIMES as much current (amperage) to produce the same horsepower! Circuit losses due to resistance, would increase SIXTEEN TIMES, if resistance remained the same, resulting in less range . (This resistance could be reduced, by using heavier, more expensive conductors and controllers, further increasing weight, size, and expense) This is also why low voltage is not used for large, high-power household appliances, such as electric stoves and electric water heaters. The VECTRIX scooter uses 125-150 volts because of this, to obtain its high horsepower rating.-Bob

Here is a (Somewhat extreme) example of the differences in performance of a circuit at 12 and 48 volts. Given that a device has a motor requiring 15 amperes at 48 volts, or 720 watts of power, and is connected to a battery of 49.5 volts with wiring, controller, and switching equipment possesing 0.1 ohm of resistance, a voltage of 1.5 volts is wasted, and converted into 22.5 watts of heat by this 0.1 ohm of resistance. Total POWER taken from the battery would be about 742.5 watts to operate the 720 watt motor, using this example.---Now, lets drop voltage, keeping the same resistance, and operating a 12 volt system, with a 13 volt battery voltage (fully charged lead-acid batteries have voltages higher than marked)-with a current of 65 amperes, we lose 6.5 volts across the wiring resistance, leaving only 6.5 volts, or 1/2 of the battery voltage, to operate the motor! With 6.5 volts, at 65 amperes, our motor gets only 422.5 watts, with another 422.5 watts being wasted as heat in the resistance! Total power drawn from the battery is now 845 watts, and our efficiency is only 50%, but at 48 volts, we got over 95% efficency, using the same wiring! With this circuit, full-power is not attainable at the lower voltage, due to excess circuit resistance, because any attempt to further increase current beyond 65 amperes will further DECREASE power and voltage available to the motor!--Bob
PS:65 amperes, rather than four times the origional 15 amperes,(60 amperes) was used to come as close as possible to the origional motor power with the 12 volt system. Using 60 amperes, the figures are: Voltage lost due to resistance is 6.0 volts, motor gets 7.0 volts if battery was at 13.0 volts as before, and motor power is 420 watts, with 360 watts wasted as heat in the resistance, and total power from the battery is 780 watts!-Bob

And/or use a timer to shut off the charger after a pre-determined time interval... IE if you had a fully charged pack and only drove it say... 5 miles, that should require no more than a couple of hours charge at the most.

This has been the solution that I could understand and implement easily. I have a countdown timer that I have attached to the power cord and I'll set a few hours of recharging after riding the bike.

I am interested in the in-depth discussion and intricacies of the batteries of this forum.

If you wired the batteries in parallel, but only during charging, and used a suitable charger, the bike would perform as it does now, if they were changed back to SERIES during operation. If they were to REMAIN in parallel, it is possible(likely) that the bike would FAIL to operate at all, as the resulting voltage would be well below design value. If it did operate, speed/power would be VERY low. Generally speaking, it is NOT very practical!-Bob

Buzzer.. long story short....
To perform the way it does the xb-600 needs to be supplied with at least a 48V battery pack.
The ONLY reason parallel was brought up is because it is the EASIEST way to charge several batteries at once and avoid any meltdowns etc.
You MUST have the batteries in series to run the bike!!!!! It will NOT run at 12V no matter how many Amp Hours it is!!!!

To the Relay questions... I considered this as well, but you would be adding in at least 3 new devices that could cause problems with its operation. If you are keeping the bike at 48V rewiring with the Anderson Powerpole method is easy as pie. Its only when you have the 1 other batter under the seat that makes any problems with longer wires. And If you ever rewire the bike, I would suggest NO LESS than 12guage wire, with 10guage being my suggestion.

In theory that would be a great solution.. Although I do not believe they exist, at least not to the general public at a reasonable cost. Even Lithium Ion batteries are made up of individual 1.5V cells wired together. There really is no EASY way or any one way to maintain your battery pack, it is all up to the individual. With just a little work however, using the powerpole method would make charging etc as easy as unplugging 1 wire harness from the battery pack and connecting the charger to the pack. I am not sure of the price of the battery maintainers mentioned on this site... there was a link to them but no pricing. Basically you connect 1 between each batter of a pack, so you would need 3 for a 4 battery pack. They are very efficient (meaning that you wont notice any drain of the pack from using them), and they monitor each battery and if one is under voltage compared to the others they correct it. They also DO work while charging the pack in series (IE with a 48V charger) as well as while being drained with use of the bike.

IMHO, depending on price of the Battery maintainers, they would probably be the easiest way to keep the pack in good condition.
The series/parallel wiring method is a good 2nd but does need a little more knowledge of basic battery and electrical theory and wiring.

The absolute easiest is to use a timer on your charger and occasionally test the individual batteries with a multi-meter, charging them individually as needed.

So translated into English (I'm an artist, not an electrician, remember), if I were to rewire my XB-600 batteries in parallel to minimize the risk of thermal meltdown, AND CHANGE NOTHING ELSE ON THE BIKE, what would I lose? Speed? Range? Power?

You would lose ABSOLUTELY NOTHING except worry about losing pack balance. The connection to the scoot is thorough a jumper plug that re-wires the batteries in series as the scoot needs and expects. This plug is removed and replaced with another that connects all four (or five or six) batteries in parallel to that single, high quality 12V charger.

It does require digging into the pack and fabricating plugs and mounts for the AndersonPowerPole connectors.

Couldn't you use this circuit that I put on paper to allow you to charge in parallel and still be wired in series. It would require 3 spdt switches and 1 spst switch you can get pretty cheap at the automotive store. ( Correction) You would need to add 2 more spst switches in the parallel circuit for this concept to work. I guess I draw this wrong when I posted it. Sorry

Your diagram cannot work as drawn, both positive and negative paths need to be broken to rewire the pack, otherwise, you will have opportunity to short the packs. High amp switches could work, but, at no time should the opportunity exist to create a dead short across any battery, or it could be very messy. DPDT with Center off might be better choice. DANGER!!!, use of switches could allow a mismatched parallel combination of 12V and 24V or 36V packs!!! Switch systems MUST Fully disconnect one mode before connecting the other to avoid exploding batteries!!! Did anyone else chuckle at the concept of an "extreme" example given in an XB-600 thread? (sorry, had to )

Your right, Didn't see this last night, it was late I guess when I put this idea to paper. You would add 2 more spst switches in the parallel circuit to break those connections. I think this will fix the problem. If there is another problem, please expalin.

I understand that the system is set to have different voltages depending on the switches. The user of this idea would have to correctly manage turning the switches on and off accordingly to charge properly. The use of switches is much cheaper than using relays when dealing with this much current.

The switches would work, but are potentially very dangerous. I've been using PowerPoles and the Parallel/Series method on 24V, 36V, and 48V scooters for over a year. I disconnect the "run" plug, and connect the "charge" plug, and there is NO CHANCE that any battery is going to be connected wrong and explode. The wiring is very straightforward and powerpoles are easy (and fun) to work with.

I have thought of/and still may decide to try a "Switch or relay" method. The reason I might do it that way is because having a 5th battery so far away from the main pack makes powerpoles a pain in the butt!!!! My main concept was this.... Using DPDT relays(or switches with a center off) to switch back and forth... the main problem with using ONLY switches is this... To get the switches in a reasonable position to be accessible the wire length is greatly increased. Using Relays (which is essentially a switch activated with a voltage rather than a physical push) allows you to leave them safely hidden where they belong.

Then... TO AVOID incorrect charging!!!!!! Make the relays connected to an actual physical Switch that BLOCKS THE CHARGING RECEPTACLE!!!! So that in order to plug in the charger you must physically move the switch to the other position. As long as the relays are rated in the 30-40A max range you should be fine. I must admit I do not know what happens to relays if//when they go bad???? Do they get stuck in one position??? or do they stop working all together for safety???? If they can get stuck in one position if the go bad, then this adds a HUGE risk factor to using relays!!!!

I still say for someone using just the 48V stock pack, that taking the time to rewire it with a Powerpole cable connector and 10 gauge wire is absolutely worth the time and effort!!! You can even route the cable to a different location to make it as easy as disconnecting the cable connected to the bike and connect it to your 12V charger that has been modified with a custom powerpole connector. It would take about a whole 20 seconds to do this once all the preliminary work was done.

I came up with another circuit using three dpdt switches to accomplish what we are talking about. I also looked into using relays to do this but I found that dpdt relays are expensive. I think you could use spdt relays 40 amp which are inexpensive but it would take nine of them in the circuit I am working on. I will post the drawings later to see what you guys think.

Here is the dpdt switch circuit I was working on with 5 batteries. I think it is drawn correctly. A little sloppy but I think it is correct. You could replace the switches with SPDT 40 amp relays since they are not very expensive. I think you would need nine to do this. Since I would wire 4 off the ignition switch to make the series connection. Then wire the other 4 for the parallel connection but you would need one to throw a ground to make the 4 parallel relays activate when the ignition is turned off. I think that would work. ]

I've got just two words for you: "Failure mode." If one of those switches doesn't "break" before the others "make" you are going to have some exciting moments.

Also, count the number of contacts. Ever looked into what the contact resistance of a switch is? How about after x number of cycles? The alternative, Anderson PowerPole connectors, are silver plated, with an "external" spring to provide consistent contact pressure, and with a wiping contact design that puts the make/break contact point away from the current carrying contact point.

Remote fifth battery? No problem, though you would either add another PowerPole set to link the remote battery to a common 10-conductor plug gang or set up your fifth battery with a single PowerPole set that would be linked in to the series plug, as in this sketch:

(I clipped the battery side connector to the battery box, and cut an opening big enough to plug the PowerPole connector directly in. Doing it again, I would put the battery side cables longer so that both sides of the connector could be out where I could see them. 2 years use of this setup, no worries.)

I agree the anderson powerpole looks like a good idea. no doubt. I still think doing a circuit with relays run off the ignition would be more convenient so you don't have to mess with plugging and unplugging anything to charge. The switches would work as long as you flipped them all on then started the bike. You would flip them all down after the bike is off to begin charging. I have a SPDT switch now installed between the 48v pack and the 5th battery. I flip it off to isolate the 5th battery and charge it with a different 12v charger. Works great. I agree that a faulty switch would be a very bad thing.

Not to hammer it too much, but you'll be plugging and unplugging anyway. Why not make it absolutely fail-safe? (BTW, I kept the stock chassis plug, and I use the stock charger for "opportunity charging" while on the road.)