Quote from: tagsoup on October 26, 2023, 01:19:56 PM

Quote from: Naranja_CT5+ on August 28, 2023, 07:47:35 AM

It seemed the chatter regarding this issue has died down..... So has RAD Power Bikes resolved this issue?

I thought adding a circuit breaker style fuse like what you see on household powerbars is a simple solution that doesn't require redesigning the battery.

I think Rad fixed it. Today I thought my battery was toast so I took it down to the retail outlet. Actually, inadvertently, I'd activated the "ship" mode, and I needed to depress the battery button for ten seconds to turn the thing on again.  The manager at the store said that Rad had changed things such that a mistaken key placement or connecting to a charger wrong will no longer burn out a fuse. I'm not going to test it to see if I have one of the new style batteries but I'd think the issue will come up with much less frequency as the old batteries reach the end of their lifespan or get fried.

I'm putting a little flap of inner tube over the charging hole, one more impediment to wrong key placement, and I'll forever more be plugging everything with a charger first into the charger then into the outlet.

It took them long enough.

As I pointed out two years ago, Rad added protection diodes to the Standard Battery BMS that prevents reverse current flow through the charge port. For some reason, they dropped them again in the Semi-Integrated Battery. Simple, cheap protection from shorts.

Quote from: satsujinsha on October 26, 2023, 07:00:31 PM
Inoxa - ahhh thx gotit. Now that I understand you were suggesting to tear it down far enough to remove individual battery cells, I'm sure I can find something (with some searching).  First, Im going to try DickB's suggestion to charge at the tabs.

DickB - I ordered some parts - a female 5.5 x 2.1mm DC charging port and a 1k ohm resister.  Once that arrives I'll piece it together.  Once assembled I'll post a pic of both the charging circuit with the resister *and a pic of the tabs across which I believe I should charge.  If you'd help validate my plan at that time (before I do anything stupid) I'd be grateful.  Prolly be a cpl days.

Really cannot overstate my appreciation. Thanks again to you both!

Just be sure to get the polarity right. Monitor voltage on the individual cell groups when charging. At trickle charge it will take quite a while to charge. If you don't see an increase in voltage after 15 minutes, one or more cells in the group is likely bad. If you see an immediate jump to 3V or more, one or more cells in the group is likely bad. I would stop trickle charging at about 3V and move on to the next cell group. Accidently shorting a charged cell group will yield bad results, so take care. Take advice on this at your own risk.

With the cells that low, I don't know if a BMS is going to allow charging. You can try trickle charging individual cell groups through the tabs. Using the Rad charger and a 1K ohm resistor would charge a cell group at about 50 mA.

Quote from: satsujinsha on October 22, 2023, 02:48:52 PM
Finally getting around to poking at this.  Looks like all the cell groups are registering zero (or, more accurately per attachment, between 30-1800mV) volts.  I wonder if this is because I've left the key in the on/lock-engaged mode and the batteries might have trickled out?

The replacement BMS has arrived, but I'd like to dive into the battery-group voltage issue.

* Does anyone have any suggestions for troubleshooting zero voltage? 
* Is there a way - or is it even wise - to charge the battery groups one-by-one and see if any of the cell groups are damaged?  Would this introduce a threat of unbalanced groups?

First, does the battery not charge?

Quote from: Radding Along on October 10, 2023, 09:29:45 PM
It?s a known issue on Rad bikes with the batteries that allow you to switch them off with a key.

If you turn the bike off at the battery instead of the handlebar switch, you run the risk of the display resetting. It doesn?t happen all the time, but it will happen eventually. For some, it happens quite often.

Turn the bike off at the handlebar switch and you will never have the issue.

No, the display is defective. I've been switching my Rover 5 off with the key virtually every day for 2 years and 6000 miles no problem. It will not happen eventually.

Quote from: gera tho on October 04, 2023, 05:40:25 PM
Moparherb has it exactly right. The motor has to be turned off on the LCD Display Remote before you turn it off with the key. Moparherb calls that discharging the controller or maybe it just has that effect but it prevents screwy things from happening like the odometer reseting itself to zero. Mine reset just after 300 miles and I had just been turning everything off with the key up till that point. I searched online for a possible answer and found this forum first and news that it MIGHT be a possible defect and Rad replaced one user's LCD display (I have a RadCity4). I finally got through to Rad tech support through their online Chat and Rad said that the displays were not defective - exactly - but prone to zeroing out the Odometer if you shut down with just the key. I don't know how moparherb picked up on this (I don't see it in the manual) but Rad said to hold the middle Mode button on the remote for 2-3 seconds to turn off the display before turning the key off. I always key off and take the battery inside to recharge after a ride. I will re-post again if this solution doesn't hold up.

I don't buy this. I've been shutting mine off with the key after daily rides for more than 2 years and 6000 miles.

Quote from: satsujinsha on October 04, 2023, 07:23:28 PM
Thanks so much for your awesome walk-thru on drive.

I believe I have a BMS issue described here: https://www.radowners.com/index.php/topic,9624.0.html#msg23799 described



I've just ordered the controller you mentioned from green bike kit..... wish me luck!

A faulty cell can give the impression that the BMS is bad. You should measure the voltage of each cell group before replacing the BMS.

Quote from: John Rose on October 03, 2023, 10:48:20 PM
But - is there some feature for dealing with a failure in one of the cells in a group of four?

No.

In comparison to the motor, headlight current is negligible.

If upgrading to the Rad Premium headlight, the controller can handle it.

Quote from: Naranja_CT5+ on September 06, 2023, 09:14:55 AMif I wired 2 headlights in parallel would the current double up?

Yes. I would be concerned about exceeding the headlight power rating of the controller.

The charger is CC/CV (Constant Current/Constant Voltage). If you plug in to the battery first, the charger will start in Constant Current mode limited to 2A. If you plug the charger in first, it will be in Constant Voltage mode, and present 54.6V to the charge connector. If you plug that into a discharged battery, the large voltage difference between battery and charger will generate a large current spike that may or may not be sufficient to blow the charge fuse.

The charger should have protection against this type of current spike in my opinion.

3A is fine for Rad batteries. Standard batteries have 5A charge fuses, and semi-integrated have 10A charge fuses. The Rad BMS will shut down on overcurrent.

It will not hurt it to use it on less than a full charge. For longevity, avoid fully draining.

The voltage of Li-Ion cells depends upon their State Of Charge (SOC) - how much energy is in them - and how much current is being drawn. Refer to the chart for a Panasonic cell. The SOC can be estimated by measuring the cell (or battery) voltage.

The Rad battery indicators are simple voltmeters, and are meant to be read with no current draw.  This from Rad:

"Check the gauge when the bike is not moving. The LCD display gauge calculates battery life based on the battery power output (instantaneous voltage reading) and can fluctuate while riding if power demand and/or output changes. If you are riding, the battery reading should stabilize at the current battery capacity after about 5 seconds when power assist is off (pedal assist 0 and no throttle applied), the brakes are not activated, and while coasting on the bike."

https://radpowerbikes.zendesk.com/hc/en-us/articles/360006192213

The Rad battery meters are not linear. My chart showing battery voltage vs SOC was made via discharge tests on my Rover 5, and the battery indicator readings determined by substituting a variable power supply for the battery. Note that the bar-type meters can only show a range - for example, 4 bars is anywhere from about 48V to 50.5V, or 50% to 70% SOC.

Just leave it as is, partially charged.