P0A80 code for good HV battery?
#32
07-28-2018, 11:06 AM
Re: P0A80 code for good HV battery?
EDIT: Added the Prolong link below.
Hi Keith,
I am following this more elaborate process you outlined above. One question regarding the change threshold from 200W to 100W bulbs. According to the below, 75W bulbs can be used down to 169V, whereas the above recommends switching to 40W bulbs at 204V itself. Curious if there's a reason why I couldn't use 100W down to say, 180V and then switch to 40W bulbs. Would the discharge move too rapid if I waited until 180V or so to switch to 40W?
https://hybridautomotive.com/pages/sd
Thanks in advance.
Again, I vigorously encourage you to record times to:
245V (3 discharges)
224V (3 discharges)
204V (3 discharges)
163V (termination of first discharge as well as when 2nd and 3rd pass through it)
102V (termination of 2nd and 3rd discharge)
IMHO, the recommended discharge to 20V is not necessary. I rarely find benefit discharging below 0.5V/cell. It can get you a little more goody out of the worst cells, but it's not necessary, and on a severely deteriorated battery, it could drive marginal modules to failure when they might otherwise mostly work.
I modify the recommendations here:
https://hybridautomotive.com/pages/sd
as follows:
Above 224V, up to 200W
Above 204V, up to 100W
Below 204V, up to 40W
ALWAYS use the same wattage bulbs in both sockets.
If you want easy mode and don't mind the wait:
100W bulbs down to 204V
40W bulbs below 204V
Whatever you do, be consistent.
When you switch bulbs, the voltage will rise initially. Ignore this. Simply record the total time to the target voltages.
Lastly, the first discharge is going to take a LONG time. I would allow for 12-20 hours. This will take so long because a large portion of the process will occur at lower current/voltages. After reconditioning, subsequent discharges should take less time as the discharge is occurring at higher voltage/current. You should notice a BIG drop in the higher wattage phase of discharge time from 1st to 2nd if the battery is responding well to reconditioning.
If all your discharges take a long time with little or no reduction in discharges times above 204V, then this is evidence of little/no response to reconditioning and indicates damage.
Lastly... if you really want to get detailed, you can do the discharge with the cover off and check individual module voltages at those prescribed pack voltages. This can really help you identify good/bad modules.
245V (3 discharges)
224V (3 discharges)
204V (3 discharges)
163V (termination of first discharge as well as when 2nd and 3rd pass through it)
102V (termination of 2nd and 3rd discharge)
IMHO, the recommended discharge to 20V is not necessary. I rarely find benefit discharging below 0.5V/cell. It can get you a little more goody out of the worst cells, but it's not necessary, and on a severely deteriorated battery, it could drive marginal modules to failure when they might otherwise mostly work.
I modify the recommendations here:
https://hybridautomotive.com/pages/sd
as follows:
Above 224V, up to 200W
Above 204V, up to 100W
Below 204V, up to 40W
ALWAYS use the same wattage bulbs in both sockets.
If you want easy mode and don't mind the wait:
100W bulbs down to 204V
40W bulbs below 204V
Whatever you do, be consistent.
When you switch bulbs, the voltage will rise initially. Ignore this. Simply record the total time to the target voltages.
Lastly, the first discharge is going to take a LONG time. I would allow for 12-20 hours. This will take so long because a large portion of the process will occur at lower current/voltages. After reconditioning, subsequent discharges should take less time as the discharge is occurring at higher voltage/current. You should notice a BIG drop in the higher wattage phase of discharge time from 1st to 2nd if the battery is responding well to reconditioning.
If all your discharges take a long time with little or no reduction in discharges times above 204V, then this is evidence of little/no response to reconditioning and indicates damage.
Lastly... if you really want to get detailed, you can do the discharge with the cover off and check individual module voltages at those prescribed pack voltages. This can really help you identify good/bad modules.
I am following this more elaborate process you outlined above. One question regarding the change threshold from 200W to 100W bulbs. According to the below, 75W bulbs can be used down to 169V, whereas the above recommends switching to 40W bulbs at 204V itself. Curious if there's a reason why I couldn't use 100W down to say, 180V and then switch to 40W bulbs. Would the discharge move too rapid if I waited until 180V or so to switch to 40W?
https://hybridautomotive.com/pages/sd
Thanks in advance.
#33
07-28-2018, 02:02 PM
Re: P0A80 code for good HV battery?
Crap can start to go bad around 1.2V/cell even under the fairly light load of the 100W bulb. Too many people have the higher wattage bulbs in and fall asleep, forget to check, etc. They show up to a pack at 2V. It's not always a problem, but it can push a marginal cell over the edge.
If you're really in a hurry, 100W down to 185V, but watch it like a hawk.
IMHO, once you're at 1.2V/cell, limiting discharge current to about 0.3A (2X 40W in series) gives the best results with minimum stress to the cells.
If you use the car to shortcut the discharge process, it makes it a little trickier to capture meaningful time/voltage data, but what you should see is that the low wattage bulb discharge times reduce significantly.
If you're really in a hurry, 100W down to 185V, but watch it like a hawk.
IMHO, once you're at 1.2V/cell, limiting discharge current to about 0.3A (2X 40W in series) gives the best results with minimum stress to the cells.
If you use the car to shortcut the discharge process, it makes it a little trickier to capture meaningful time/voltage data, but what you should see is that the low wattage bulb discharge times reduce significantly.
#34
07-28-2018, 02:16 PM
Re: P0A80 code for good HV battery?
Thanks, Keith. I will follow the conservative approach. Also, for bulb changes, is it OK if I first disconnect the discharger from the battery harness and reconnect after I have the lower wattage bulbs in? I am afraid I may not be able to unscrew the higher wattage bulbs fast enough on reaching the target voltage.
Thanks in advance.
Thanks in advance.
#35
07-28-2018, 02:22 PM
Re: P0A80 code for good HV battery?
Yes, that's fine. Once you have the lower wattage bulbs in and connected to the harness, the voltage will continue to rise for a bit. This occurs because you've reduced the load on the battery and something you shouldn't worry about.
Also, for convenience, you can always use the orange safety plug as a master ON/OFF switch.
Also, for convenience, you can always use the orange safety plug as a master ON/OFF switch.
#36
07-28-2018, 05:16 PM
Re: P0A80 code for good HV battery?
Thanks, Keith. Since you are recommending the third discharge to terminate at the same 102V as the second discharge, would the third discharge to the same voltage really buy anything? IOW, should I just stop with the second discharge (followed by balancing)?
#37
07-28-2018, 06:48 PM
Re: P0A80 code for good HV battery?
#38
07-29-2018, 11:19 AM
Re: P0A80 code for good HV battery?
Hi Keith,
The First discharge finished just now. Here are the numbers:
(Started with 200W Bulbs at 287V; Duration times below are NOT cumulative, i.e., they are relative to the previous listed voltage point)
245V - 1 hour 11 mins
224V - 23 mins (Switched to 65W bulbs here)
169V - 4 hours 5 mins (Switched to 25W bulbs here)
163V - 2 hours 28 mins (Discharge cycle terminated here)
Total time: 8 hours 6 mins
Also I am curious about the discharge potentially going faster tomorrow. I would have thought that with potentially some capacity increase, the 2nd discharge cycle should potentially take more time?
Will report on the second discharge tomorrow.
Thanks.
The First discharge finished just now. Here are the numbers:
(Started with 200W Bulbs at 287V; Duration times below are NOT cumulative, i.e., they are relative to the previous listed voltage point)
245V - 1 hour 11 mins
224V - 23 mins (Switched to 65W bulbs here)
169V - 4 hours 5 mins (Switched to 25W bulbs here)
163V - 2 hours 28 mins (Discharge cycle terminated here)
Total time: 8 hours 6 mins
Also I am curious about the discharge potentially going faster tomorrow. I would have thought that with potentially some capacity increase, the 2nd discharge cycle should potentially take more time?
Will report on the second discharge tomorrow.
Thanks.
#39
07-29-2018, 01:36 PM
Re: P0A80 code for good HV battery?
If you're recovering capacity and not suffering from widespread damage, all discharging above 204V should take longer because more capacity is available. Discharging below 204V should be shorter.
Estimates (:
287-245V = 1.97Ah extracted (about 1.6A w/200W bulbs)
245-224V = 0.61Ah extracted (about 0.5A w/65W bulbs)
224-169V = 2.21Ah extracted
169-163V = 0.50Ah extracted (about 0.2A w/25W bulbs)
Total: 5.29Ah extracted.
If the discharge is recovering capacity, MOST of that will move above 204V.
On the second discharge, probably worth trying to get an approximate time to 204V in addition to the other times you collected. This will better approximate your actual pack capacity.
Estimates (:
287-245V = 1.97Ah extracted (about 1.6A w/200W bulbs)
245-224V = 0.61Ah extracted (about 0.5A w/65W bulbs)
224-169V = 2.21Ah extracted
169-163V = 0.50Ah extracted (about 0.2A w/25W bulbs)
Total: 5.29Ah extracted.
If the discharge is recovering capacity, MOST of that will move above 204V.
On the second discharge, probably worth trying to get an approximate time to 204V in addition to the other times you collected. This will better approximate your actual pack capacity.
#40
07-29-2018, 03:18 PM
Re: P0A80 code for good HV battery?
Thanks, Keith. Got it now, on the capacity thing. I had 204V written down on the sheet for recording the time as well as switch to 25W bulbs, but on the fly decided to wait till 169V for the bulb change and in the process forgot to record the time at 204V. Will capture this as well for the next 2 discharges. Thanks again.
