ElectricMotorcycleForum.com
Makes And Models => Zero Motorcycles Forum | 2013+ => Topic started by: herculeesjr on May 03, 2021, 03:18:02 AM
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It was a nice Saturday night and I wanted to go for a ride. I wanted to just cruise and see how far I can ride going 75mph on the interstate with saddlebags and everything else attached, plus I wanted to measure how many KWh go back into the bike charger with a fully depleted battery. So I rode nonstop one direction on the interstate with Custom mode set to 75mph. Once I reached 45% I took the next exit to turn around and headed back home. I was at 4% battery left on the dash pulling off the interstate and an average of 135Wh/mile. It was constant 75mph with zero slowdowns except taking the exit to turn around at the halfway point, mostly level terrain too.
I rode further doing 55mph till it dropped to 0%, dash said I had 4.8miles left. I then rode around town within a mile of my house till it dropped to 1.2miles left and I rode back home not wanting to push it further or literally have to push it home. A total of 60miles riding from 100% to 0% on the dash with 1.0miles range remaining once I parked.
I pulled the logs; when I pulled in the driveway and parked the logs state I still had 3% battery left (0% on the dash) with a battery voltage of 93.696v, and 1.0miles of remaining range on the dash. So unlike what multiple forum posts state, 95.000v is not battery pack minimum. I'm curious if anyone has done any research as to what the real battery cutoff voltage is?
Also, the charger took 9.87KWh to fully recharge the battery, but I can't find any other posts where people measured how many KWh were used to recharge their bike from dead to full. I have a 2017 DS ZF13.0.
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Well technically the cells are good down to 2V so that's 56V for all 28 cells, plus a little bit because they won't be perfecting balanced and some will be above that minimum. However that's just the resting voltage and it will sag under load to below that minimum so for actual usage it would need to cut out a fair bit higher than 2V.
As for the state of charge reading it's not an instantaneous measurement of the battery voltage because then it would jump around constantly, dropping under load and then recovering. Like wise while your battery may have dropped to 93V it probably would have recovered to 95V or more if you let the bike sit for a while. As the Unofficial Manual states the SoC can be correlated to a certain voltage at rest, but under an actual load there will be filtering and averaging going on.
https://zeromanual.com/wiki/State_of_Charge
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Looking through your link, followed by a ton of looking around the unofficial manual website, I found this "Zero will let you discharge to about 88 volts" at https://zeromanual.com/index.php?title=BMS/SoC_Estimation .
So I guess the bike had a decent bit of life left in it before it cut out and shut down, but I'm not sure I want to ride around that low ever again. I pulled the BMS logs today to see the full discharge and then recharge. This was at its lowest:
07947 05/01/2021 19:02:22 Discharge level 092 AH, SOC: 2%, I:000A, L:3432, l:3447, H:3449, B:017, PT:039C, BT:034C, PV:96425, M:Bike On
07948 05/01/2021 19:02:22 SOC:88224,89877,92553,104000,12,5,2,17
07949 05/01/2021 19:02:22 Discharge cutback 45%
07950 05/01/2021 19:02:22 354AWhich I'm not sure what most of that means, I imagine more digging through the unofficial manual will give me a breakdown on all those numbers. This is right before the charger shut off:
08058 05/02/2021 02:49:14 Discharge level 000 AH, SOC:100%, I:000A, L:4153, l:4149, H:4160, B:007, PT:026C, BT:044C, PV:116432, M:Idle
08059 05/02/2021 02:49:14 SOC:0,94677,0,104000,100,100,100,-5
08060 05/02/2021 02:49:33 Voltage Across Contactor: 104467mV (Okay)
I think it's saying I was limited to 45% of max torque, 2% charge remaining, lowest cell was 3.432v, highest cell was 3.449v, 96.425v pack voltage, and I had used 92Ah from the battery (not sure if that includes regen)? Which suggests like you said the bike sitting let voltage go back up a bit.
With this info how can I go about comparing my battery capacity to a new battery pack?
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A 2017 would use 29Ah cells. So if that 92Ah used is correct then I would assume 4x 28 cells in series for a total of 116Ah, and with that large a difference I would also assume regen is probably taken into account.
You're correct on most of those other points, although it wouldn't be 45% torque because the power needed to achieve that amount of torque will vary so it will just be 45% of whatever the maximum current draw is (I think about 460A continuous and 800A for 10 seconds) and thus 45% power. The PT and BT relate to temperatures, PT probably being pack temperature because PV is pack voltage but not sure what BT would be. B would be the difference in cell balance, so 0.017V when discharged and 0.007V when fully charged. The lowercase l is probably the average voltage.
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A 2017 would use 29Ah cells. So if that 92Ah used is correct
That may be what Farasis stamps on the cells but Zero's BMS only uses 26Ah. The ZF13 is a 104Ah pack. The ZF14.4 cells are recognized as 28.5AH by the bike for a total of 114Ah.
Seeing that the 13 pack is 104Ah with a nominal 102vdc, I would expect a full charge to be no more than 10.6kWh.
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So if I wanted to do a completely perfect battery health test I would want to disable all regen and redo this test, getting as close to 88v as possible, then seeing how many Ah I used in the BMS logs? Or is there a more preferred way? I can't seem to find any complete info on how to test the battery health so I guessed up most of this.
I don't believe there is anything wrong with my battery, I'm just curious to find out how good of condition it's in since I'm now the bikes third owner.
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The standard capacity test I recommend is to buy or borrow a Kill-A-Watt meter. Ride the bike to empty. As in it absolutely refuses to go any further. Done. Dead. Finito.
Attach the meter to a wall outlet and do a full charge with the onboard charger. Report those numbers back here.
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I found my old post regarding riding my 2018 Zero S with PT down to "00" SOC and then recharging it overnight. A full recharge took 15.1 kWh at 120V as measured by a Kill A Watt meter: https://www.electricmotorcycleforum.com/boards/index.php?topic=8343.0
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Hm. That's actually a bit higher than I would have expected.
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Well with my battery pack down to 93-95v and a full overnight charge it took 9.87kWh from the outlet. So it sounds like my battery is pretty healthy if I were to assume there was even 0.2kWh left in it from me not riding it till it was completely dead. It still said I had 1.0miles left on the dash. I'm within 1kWh of your quoted 10.6kWh.
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I’m only getting a maximum of about 6.8 kWh of charging into my ‘17 SR 13.0 so I think I have a pretty good case for a warranty replacement. I need to get a copy of last night’s power usage from Evercharge (my apartment building’s EV charger company) and then I’ll have my ducks in a row to submit a claim.
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I’m only getting a maximum of about 6.8 kWh of charging into my ‘17 SR 13.0 so I think I have a pretty good case for a warranty replacement. I need to get a copy of last night’s power usage from Evercharge (my apartment building’s EV charger company) and then I’ll have my ducks in a row to submit a claim.
I admire your independence, but Zero is just going to have the dealer or you ride it form 100 to 0 1-3 times and then look at the logs to determine if it qualifies. They don't go off of EVSE logs or Kill-A-Watt readings.
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Yeah at first they were handing out replacement 14.4s like candy but they've become a bit more strict in the last year or so.
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Good to know! Yesterday's ride was from 100 to 0 (on the dash) so that's one in the bag. I haven't pulled the logs yet so I can't say for sure what the discharge level will reveal. I'm assuming discharge level is what they go off of? Last time I had it down to 0% it said 093 Ah but I didn't start with a 100% charge so it can't be used for a claim.
To answer the OP, the ride I referenced was the kind of real "stick a fork in it" 0% that MVetter was talking about. The bike kept shutting off if I didn't operate the throttle with a surgeon's hand until I was eventually riding in the bike lane at 15-20 MPH and accelerating like a snail on quaaludes. Before it shut off for the last time and had to be pushed the remaining 3 blocks to my place, I had the pack voltage down to 90.6:
05045 04/04/2021 19:15:22 Riding PackTemp: h 37C, l 34C, PackSOC: 0%, Vpack: 90.621V, MotAmps: 60, BattAmps: 64, Mods: 10, MotTemp: 42C, CtrlTemp: 20C, AmbTemp: 6C, MotRPM:3407, Odo:72972km
Corresponding BMS log if anyone's curious:
[spoiler]91211, M:Bike On
06212 04/04/2021 19:23:32 SOC:82088,81015,93305,104000,11,0,0,23
06213 04/04/2021 19:23:32 Discharge cutback 4%
06214 04/04/2021 19:23:32 30A
06215 04/04/2021 19:24:04 ERROR: Discharge Overcurrent: 52A ( limit=30A )
06216 04/04/2021 19:24:04 DEBUG: Entered Discharge Fault State
06217 04/04/2021 19:24:04 DEBUG: CAN NOT Receiving Syncs
06218 04/04/2021 19:24:05 Contactor was Opened Pack V: 91048mV, Switched V: 91057mV, Prechg Pct: 100%, Dischg Cur: -7250mA
06219 04/04/2021 19:24:06 DEBUG: CAN Receiving Syncs
06220 04/04/2021 19:24:29 DEBUG: CAN NOT Receiving Syncs
06221 04/04/2021 19:24:34 Voltage Across Contactor: 24921mV (Okay)
06222 04/04/2021 19:24:36 System Turned Off
06223 04/04/2021 19:24:36 DEBUG: CAN Link Is Down
06224 04/04/2021 19:24:37 Discharge Overcurrent Cleared
06225 04/04/2021 19:24:37 DEBUG: Entered Idle State
06226 04/04/2021 19:24:40 System Turned On
06227 04/04/2021 19:24:40 Rev:34,Build:2018-08-24_095615 506 banka
06228 04/04/2021 19:24:40 Pack:2016_monolith,Numbricks:4
06229 04/04/2021 19:24:40 DEBUG: Entered Running State
06230 04/04/2021 19:24:40 Discharge level 093 AH, SOC: 0%, I: 0A, L:3177, l:3197, H:3317, B:140, PT:037C, BT:033C, PV: [/spoiler]
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That seems to line up with the SOC page in the unofficial manual then. It states you can go down to roughly 88v before the bike absolutely quits, with 0% charge being at 92.4v. you were down below the "0%" where as I expected things can get tricky as it's more of a limp home mode.
I need to order a USB OBD adapter so I can see the BMS stats, just since I'm not actually having issues it hasn't been high priority.
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Reading your first post, I do not think you are interested in your minimum pack voltage.
You probably want to ride until the bike refuses to start. Then you will know your "range".
The bike (at least the zero s 2019) will protect itself from having discharged too far.
I have a feeling that the BMS and the percentage on the display re aligns on; a. how its programmed and b. experience how far the BMS can go.
MBB
03374 11/15/2020 20:31:15 Riding PackTemp: h 33C, l 28C, PackSOC: 2%, Vpack: 94.76V, MotAmps: 37, BattAmps: 21, Mods: 01, MotTemp: 45C, CtrlTemp: 17C, AmbTemp: 5C, MotRPM:1868, Odo: 974km
03375 11/15/2020 20:32:15 Riding PackTemp: h 33C, l 28C, PackSOC: 1%, Vpack: 94.272V, MotAmps: 53, BattAmps: 34, Mods: 01, MotTemp: 45C, CtrlTemp: 17C, AmbTemp: 5C, MotRPM:2048, Odo: 975km
03376 11/15/2020 20:33:15 Riding PackTemp: h 33C, l 28C, PackSOC: 1%, Vpack: 92.235V, MotAmps: 189, BattAmps: 113, Mods: 01, MotTemp: 44C, CtrlTemp: 17C, AmbTemp: 5C, MotRPM:1784, Odo: 975km
03377 11/15/2020 20:34:15 Riding PackTemp: h 33C, l 28C, PackSOC: 0%, Vpack: 94.412V, MotAmps: 25, BattAmps: 16, Mods: 01, MotTemp: 46C, CtrlTemp: 17C, AmbTemp: 5C, MotRPM:1958, Odo: 976km
03378 11/15/2020 20:35:15 Riding PackTemp: h 33C, l 28C, PackSOC: 0%, Vpack: 93.532V, MotAmps: 65, BattAmps: 41, Mods: 01, MotTemp: 46C, CtrlTemp: 17C, AmbTemp: 5C, MotRPM:1962, Odo: 977km
03379 11/15/2020 20:36:15 Riding PackTemp: h 33C, l 28C, PackSOC: 0%, Vpack: 94.493V, MotAmps: 58, BattAmps: 20, Mods: 01, MotTemp: 45C, CtrlTemp: 17C, AmbTemp: 5C, MotRPM:1104, Odo: 977km
03380 11/15/2020 20:37:15 Riding PackTemp: h 33C, l 28C, PackSOC: 0%, Vpack: 93.829V, MotAmps: 259, BattAmps: 61, Mods: 01, MotTemp: 43C, CtrlTemp: 17C, AmbTemp: 5C, MotRPM: 597, Odo: 978km
03381 11/15/2020 20:38:15 Riding PackTemp: h 33C, l 28C, PackSOC: 0%, Vpack: 94.962V, MotAmps: -12, BattAmps: 0, Mods: 01, MotTemp: 44C, CtrlTemp: 17C, AmbTemp: 5C, MotRPM: 694, Odo: 978km
03382 11/15/2020 20:39:15 Riding PackTemp: h 33C, l 28C, PackSOC: 0%, Vpack: 94.477V, MotAmps: 25, BattAmps: 10, Mods: 01, MotTemp: 43C, CtrlTemp: 17C, AmbTemp: 5C, MotRPM:1253, Odo: 979km
03383 11/15/2020 20:40:15 Riding PackTemp: h 33C, l 28C, PackSOC: 0%, Vpack: 94.852V, MotAmps: -24, BattAmps: -5, Mods: 01, MotTemp: 43C, CtrlTemp: 17C, AmbTemp: 5C, MotRPM:1021, Odo: 979km
03384 11/15/2020 20:41:15 Riding PackTemp: h 33C, l 28C, PackSOC: 0%, Vpack: 94.261V, MotAmps: 30, BattAmps: 12, Mods: 01, MotTemp: 42C, CtrlTemp: 17C, AmbTemp: 5C, MotRPM:1156, Odo: 980km
03385 11/15/2020 20:42:15 Riding PackTemp: h 32C, l 27C, PackSOC: 0%, Vpack: 93.985V, MotAmps: 32, BattAmps: 14, Mods: 01, MotTemp: 42C, CtrlTemp: 17C, AmbTemp: 5C, MotRPM:1337, Odo: 980km
03386 11/15/2020 20:43:15 Riding PackTemp: h 32C, l 27C, PackSOC: 0%, Vpack: 93.99V, MotAmps: 32, BattAmps: 12, Mods: 01, MotTemp: 42C, CtrlTemp: 17C, AmbTemp: 5C, MotRPM:1194, Odo: 981km
03387 11/15/2020 20:44:15 Riding PackTemp: h 32C, l 27C, PackSOC: 0%, Vpack: 94.409V, MotAmps: -16, BattAmps: -2, Mods: 01, MotTemp: 42C, CtrlTemp: 17C, AmbTemp: 5C, MotRPM: 835, Odo: 981km
03388 11/15/2020 20:45:15 Riding PackTemp: h 32C, l 27C, PackSOC: 0%, Vpack: 93.403V, MotAmps: 33, BattAmps: 14, Mods: 01, MotTemp: 41C, CtrlTemp: 17C, AmbTemp: 5C, MotRPM:1337, Odo: 982km
03389 11/15/2020 20:46:15 Riding PackTemp: h 32C, l 27C, PackSOC: 0%, Vpack: 93.337V, MotAmps: 36, BattAmps: 16, Mods: 01, MotTemp: 42C, CtrlTemp: 17C, AmbTemp: 5C, MotRPM:1290, Odo: 982km
03390 11/15/2020 20:47:15 Riding PackTemp: h 32C, l 27C, PackSOC: 0%, Vpack: 93.198V, MotAmps: 34, BattAmps: 14, Mods: 01, MotTemp: 41C, CtrlTemp: 17C, AmbTemp: 5C, MotRPM:1218, Odo: 983km
03391 11/15/2020 20:48:15 Riding PackTemp: h 32C, l 27C, PackSOC: 0%, Vpack: 92.707V, MotAmps: 43, BattAmps: 17, Mods: 01, MotTemp: 41C, CtrlTemp: 17C, AmbTemp: 5C, MotRPM:1222, Odo: 983km
03392 11/15/2020 20:49:15 Riding PackTemp: h 32C, l 27C, PackSOC: 0%, Vpack: 92.512V, MotAmps: 0, BattAmps: 1, Mods: 01, MotTemp: 41C, CtrlTemp: 17C, AmbTemp: 5C, MotRPM:1331, Odo: 984km
03393 11/15/2020 20:50:15 Riding PackTemp: h 32C, l 27C, PackSOC: 0%, Vpack: 92.447V, MotAmps: 33, BattAmps: 13, Mods: 01, MotTemp: 41C, CtrlTemp: 17C, AmbTemp: 5C, MotRPM:1260, Odo: 984km
03394 11/15/2020 20:51:15 Riding PackTemp: h 32C, l 27C, PackSOC: 0%, Vpack: 91.437V, MotAmps: 55, BattAmps: 26, Mods: 01, MotTemp: 41C, CtrlTemp: 17C, AmbTemp: 5C, MotRPM:1372, Odo: 985km
03395 11/15/2020 20:52:15 Riding PackTemp: h 32C, l 27C, PackSOC: 0%, Vpack: 91.044V, MotAmps: 176, BattAmps: 52, Mods: 01, MotTemp: 40C, CtrlTemp: 17C, AmbTemp: 5C, MotRPM: 757, Odo: 985km
03396 11/15/2020 20:53:15 Riding PackTemp: h 32C, l 27C, PackSOC: 0%, Vpack: 91.886V, MotAmps: -24, BattAmps: -6, Mods: 01, MotTemp: 40C, CtrlTemp: 17C, AmbTemp: 5C, MotRPM:1067, Odo: 986km
03397 11/15/2020 20:54:15 Riding PackTemp: h 32C, l 27C, PackSOC: 0%, Vpack: 89.645V, MotAmps: 79, BattAmps: 31, Mods: 01, MotTemp: 40C, CtrlTemp: 17C, AmbTemp: 5C, MotRPM:1174, Odo: 986km
03398 11/15/2020 20:54:33 0x1c 0x47 0x5d 0x01 0x00 0x00 0x00 0x30 0x02 0xb2 0x26 0xfd ???
03399 11/15/2020 20:54:33 - DEBUG: MBB measured 88615mV
03400 11/15/2020 20:54:33 Throttle Disabled: Low Batt Voltage,
03401 11/15/2020 20:54:55 Power Off Key Switch
BMS
00916 11/15/2020 20:54:07 Discharge level 119 AH, SOC: 0%, I:024A, L:3078, l:3137, H:3273, B:195, PT:032C, BT:026C, PV:89764, M:Bike On
00917 11/15/2020 20:54:07 SOC:114417,113295,119001,114800,0,0,0,35
00918 11/15/2020 20:54:07 Discharge cutback 4%
00919 11/15/2020 20:54:07 30A
00920 11/15/2020 20:54:33 0x05 0xeb 0x0b 0xc0 0x0c 0x20 0x1a 0x24 0xa7 0x19 0x07 0x00 0x47 0x5d 0x01 0x00 0x20 0x00 0xb2 0xc0 0xfd ???
00921 11/15/2020 20:54:33 - DEBUG: Cells - 3051, 3088, 3165, 3167, 3211, 3192, 3259, 3214, 3227, 3219, 3201, 3190, 3264, 3203, 3226, 3244, 3198, 3230, 3206, 3201, 3222, 3211, 3178, 3185, 3191, 3145, 3172, 3155
00922 11/15/2020 20:54:55 Contactor was Opened Pack V: 91581mV, Switched V: 91529mV, Prechg Pct: 100%, Dischg Cur: 1232mA
00923 11/15/2020 20:54:56 System Turned Off
00924 11/15/2020 20:54:56 DEBUG: CAN Link Is Down
00925 11/15/2020 20:54:56 DEBUG: Entered Idle State
What i'm trying to say:
- MBB and BMS are two seperate units. The MBB estimates the "range"
- A range test does not really depend on the voltage the BMS will get to, but mostly till when the BMS will provide power
!! Disclamer: I like to ride my bike till I have to walk home, once a year... Not too often. While the BMS will protect the battery, the battery will not love you for doing so.
Remember; Happy battery, Happy bike :P
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I'm definitely interested in what the minimum voltage is, which appears to be 88v, so that way I can get an estimate in my head how much range I have left before it's completely dead. Like how my truck can say "0 miles to E" on the dash but if I plug into the OBD port I can see the fuel guage is still reading 8% in the tank. It's a "reserve" that you don't want to use frequently, but is nice to know it's there and how much range it can provide in case of emergency.
It seems 92.4v is a safe low voltage, while 88v can be reached with very gentle acceleration.
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Interesting idea.
How would you determine the range you have left, if the Vpack shows 96v?
I added a plot of a different range test I did last month. I drove on the highway for a quite constant speed till 18% Pack SOC. After that I went to try my luck to see how far I could go beyond 0% and a range estimate of 0km. I did not max it out completely. but this might help you.
A nice thing to note is probably that the voltage does not decrease linearly.
I look forward to your estimation method.
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I'm definitely interested in what the minimum voltage is, which appears to be 88v, so that way I can get an estimate in my head how much range I have left before it's completely dead. Like how my truck can say "0 miles to E" on the dash but if I plug into the OBD port I can see the fuel guage is still reading 8% in the tank. It's a "reserve" that you don't want to use frequently, but is nice to know it's there and how much range it can provide in case of emergency.
It seems 92.4v is a safe low voltage, while 88v can be reached with very gentle acceleration.
That sounds about right, but don't count on being able to get all the way to 88v no matter how gently you accelerate. Mine only got down to 90.6v and wouldn't turn back on.
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When batteries are low on charge the voltage sag from applying a load can drop it below the minimum. This is of course worse in cold conditions.
-Crissa
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So I wouldn't really know how to calculate remaining range say from 95v to 90v. I'm sure there's some math that can be done by looking at the data sheet for the specific cells used by Zero, but I haven't looked into it or even thought of trying, yet. My idea was more of having the ZeroSpy app running in this emergency situation and watching the voltage as I ride, and by the time I'm down to let's say 92v I know I absolutely better find an outlet in the next half mile or find a safe place to pull over and call a tow.
From what research I have done it seems there's still multiple miles of city riding left at 95v, maybe even a bit of interstate riding, but no concrete answers on how much. Plus when you're looking at such a narrow band of voltage range compared to the entire pack charge range small variables like careful acceleration between person to person plus temperature and road incline all can have dramatic effects.
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Voltage and amperage available are not a one to one ratio. There's curves involved.
-Crissa
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So I wouldn't really know how to calculate remaining range say from 95v to 90v. I'm sure there's some math that can be done by looking at the data sheet for the specific cells used by Zero, but I haven't looked into it or even thought of trying, yet. My idea was more of having the ZeroSpy app running in this emergency situation and watching the voltage as I ride, and by the time I'm down to let's say 92v I know I absolutely better find an outlet in the next half mile or find a safe place to pull over and call a tow.
From what research I have done it seems there's still multiple miles of city riding left at 95v, maybe even a bit of interstate riding, but no concrete answers on how much. Plus when you're looking at such a narrow band of voltage range compared to the entire pack charge range small variables like careful acceleration between person to person plus temperature and road incline all can have dramatic effects.
Essentially you're trying to figure out how to calculate VSOC. I assume if that was easy Zero would have done it for us by now.
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My idea was more of having the ZeroSpy app running in this emergency situation and watching the voltage as I ride, and by the time I'm down to let's say 92v I know I absolutely better find an outlet in the next half mile or find a safe place to pull over and call a tow.
From what research I have done it seems there's still multiple miles of city riding left at 95v, maybe even a bit of interstate riding, but no concrete answers on how much. Plus when you're looking at such a narrow band of voltage range compared to the entire pack charge range small variables like careful acceleration between person to person plus temperature and road incline all can have dramatic effects.
At the start i was a bit worried that you were taking shortcuts in trying to understand the voltage of the BMS. But it sounds like you have an good understanding of it. :)
I guess in the best way is to test it in real live to see if all is behaving as you expect it. and get some experience with determining the emergency range. I think you will be fine.
I am a bit lazy,
- When I have 3% left, I will want to get away from the highway as fast as possible. (not by driving fast cuz that will drain the battery :P)
- When the battery percentage is 0% I assume I have < than 10 km left. This is the point where I start to panic and definitely want to find a charging station.
- The moment my range indicator jumps to 0 km, I assume I will have 4 km left.
Oh and I to catch the moment where i can see 1% battery left on my display. So far I always see it jump from 2% to 0% ;D
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Zeros don't like showing several SoC levels ending in 1.
-Crissa
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It also differs from one bms to another. If you ride together with two the same zeros, one will loose soc faster than the other one in the higher % , but at the end they will end at 0% very close to each other. I think the only way to know , is to test it on your bike.
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I also think that the max and min voltages depend on the firmware. Some of us experienced a different behavior of the bike after firmware upgrade.
It means that the results obtained with your bike will be hardly comparable to other bikes.
Attached you will find my report of the only 100% to 0% test that I have made with my 2016 FXS with 6.5 kWh battery, including logs, dash pictures, and Zero Voltage reports.
Note that I have kept my original 2016 firmware that works fine.
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Gt13013, how did your bike manage a 3mV cell balance at 0% SOC?
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Gt13013, how did your bike manage a 3mV cell balance at 0% SOC?
That is a good question. ??? When I rode my 2018 Zero S with PT down to an indicated "00" cell balance was 20-23 mA, although it quickly changed to 10-11 mA upon being plugged in. And that was on relatively new batteries that were well balanced before I started the ride. The only time i see 3mV cell balance is after my pack is fully charged and the OBC has turned off after balancing the cells.
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Gt13013, how did your bike manage a 3mV cell balance at 0% SOC?
That is simple: the Cell Balance indication of Zero Voltage App is completely wrong, at least for my bike, and it has been reported by several other users. I use Zero Voltage for voltage only!
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You can get the cell balance from the battery logs.
My bike has two 3.6 kWh packs, and there is a log for each pack. Here are the indications from these logs:
At the end of the experiment (with SOC 0% on the dash), and after some minutes of rest:
On the 1st pack: SOC=1%, min=3137mV, max=3257mV, unbalance=120mV, PV=89437mV
On the 2nd pack: SOC=5%, min=3117mV, max=3287mV, unbalance=170mV, PV=89456mV
And just at the end of the experiment (before the minutes of rest), the two packs where at 89245 mV and 89268 mV respectively.
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Out of boredom and a little bit of miscalculating remaining range on a ride today I did a pretty good test of voltage cutoff. I was able to do 75mph on the interstate down to about 93v (under load) and it started cutting back speed right before my exit to about 70-72mph and it had nothing left to go faster. About ten seconds of regen to a complete stop and from there I was able to do 55-60mph till around 92v (again under load) where it started severely cutting back once I hit 91.5v, at that point I was able to slowly accelerate from another red light to 40mph, then it cut me to 35mph, then 30mph. Another red light and I'm sitting around 92v waiting for it to turn green, I gently accelerate and the throttle gives out and the bike dies. I pull over and key cycle the bike then very gentle acceleration it maxes at about 15mph and around 91v I finally make it home about a mile later.
I'll pull logs after I get a full charge, I got my Kill-A-Watt meter hooked up to the charger, but I'd say right now 92v is about where the bike is now rather iffy to ride. And I know to do a bit better planning and research further if a charge station is no longer in service and to have backup stations in mind, which was my case today of not planning for a bad charge station.
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@Herculeesjr
Lots of useful info in your test. Thank you for sharing!
Do you have an estimate of distance you have traveled after hitting 92v?
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I checked the Kill-A-Watt this morning and it showed 11.55kWh after a full charge. With the 2017 ZF13.0 battery nominal capacity being 11.4kWh I'd say my battery is pretty darn healthy.
As far as range I didn't record start and end mileage unfortunately since it was a few small trips throughout the week and then one big ride yesterday. I should be able to find out range ridden when I pull the logs though.
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@Herculeesjr
Lots of useful info in your test. Thank you for sharing!
Do you have an estimate of distance you have traveled after hitting 92v?
So from 0% on the dash, which equals about 5% on the BMS, I rode 10.5miles to a low of 90.911v. About 8 miles was 75mph on the interstate, about 2miles around 50-60mph, and half a mile at 30mph. It's difficult to say how far I went from 92v since voltage fluctuates, so figures based off percentage and me measuring routes on Google Maps are much more guaranteed.
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I checked the Kill-A-Watt this morning and it showed 11.55kWh after a full charge. With the 2017 ZF13.0 battery nominal capacity being 11.4kWh I'd say my battery is pretty darn healthy.
As far as range I didn't record start and end mileage unfortunately since it was a few small trips throughout the week and then one big ride yesterday. I should be able to find out range ridden when I pull the logs though.
The ZF13's nominal is actually 10.6kWh. 104Ah x 102v = 10608Wh = 10.6kWh
So either you were super deep into that pack or there were significant heat losses in the charger.
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A 2017 would use 29Ah cells. So if that 92Ah used is correct then I would assume 4x 28 cells in series for a total of 116Ah,
These are in reality marked at 28Ah directly on the brick and not 29Ah. Also 4x 28 cells is not in serie but in PARALLEL for a total of 116Ah, ;)
Doc
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for those who are interested the kill-a-watt meter, the famous P4300 or p4400 can measure DC at the input! I have discovere that when they released the firsts unit couple years afo. and guess what? they display "DC" instead of the Hz frequency when Dc is applied.. so if some of you dont have any electronic load to measure the battery you can use that little kill a watt and a big hair dryer....
On all my Zero i have always installed a "cycle analyst", that great multi function EV display that i know well since about 14 years. And i love it it give me max current, min voltage Wh, Ah, Wh/km, speed, can also datalog with GPS etc...
On my SR 2017 with PT i will have to rebalance the cells as the lasts recharge only reach 115.6V even though at slow charging .. probably that the pack balance is not great.
Usually i measure about 13.3 to 13.4kWh from 100% to 0.0000000% on the very well calibrated cycle analyst.
Doc
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A 2017 would use 29Ah cells. So if that 92Ah used is correct then I would assume 4x 28 cells in series for a total of 116Ah,
These are in reality marked at 28Ah directly on the brick and not 29Ah. Also 4x 28 cells is not in serie but in PARALLEL for a total of 116Ah, ;)
Doc
I was just going by what the unofficial manual says, labelled as 28Ah but actually 29Ah. Also it's 28 in series to get the voltage, 4 of those series strings in parallel for the capacity.