|
Post by organist on Jul 13, 2015 9:54:42 GMT 11
Purchased my NZ-new LEAF 5 weeks ago, and have since noticed a "Weak Cell #1" - around 15mV below the other 95 pairs when in a Low Battery Warning. Effectively the other 95 cells are being stopped from discharging fully, while Cell #1 is protected from dropping below a minimum level. The State Of Charge (LeafSpy) of the battery is showing 21% when the battery is almost in Turtle Mode.
Anyone had any experience with Weak cells, and anyone had any experience with Nissan's attitude to such faults? Sadly, their standard tests don't seem to show a single weak cell, even if it ultimately affects the performance of the entire battery!
|
|
|
Post by Cachexian (Gordon) on Jul 13, 2015 23:22:57 GMT 11
That is a bit of a worry. Good to know that the bms does work to protect the weak cell though.
I'll be interested go hear Nissan's response to the problem.
|
|
|
Post by quaternary on Jul 14, 2015 8:44:32 GMT 11
Here's a couple of screen shots of organist's LeafSpy, to show the magnitude of the problem. Here is a the result of the "Cell Voltage Loss Inspection" test, where you can see the dire nature of that cell #1. Now, here's the really interesting thing - check out what happens on the summary screen when the Gids goes down. For most of us, the % Gids and the % SOC goes down in concert; but with the weak cell number 1, with only 21 Gids remaining (below the second low battery warning and representing 7.5% of the total Gids), there is still 20.8% of the SOC left. In other words, this energy in his cells is not available, presumably as a consequence of cell #1. Has anyone else experienced anything like this with their Leafs? And the other point, the warranty for the battery talks about losing "bars" and the single weak cell doesn't affect the bars... which makes you wonder about where that leaves (leafs?) us here.
|
|
|
Post by gabzimiev on Jul 14, 2015 9:31:00 GMT 11
so the self help would be to discharge and balance the pack several times. and see if the BMS can correct it.
there was a aussie who complained about loosing 1 bar after 5k km he had a dodgy cell too can't remember what happened to him.
|
|
|
Post by empowerrepower on Jul 14, 2015 11:01:03 GMT 11
so the self help would be to discharge and balance the pack several times. and see if the BMS can correct it. there was a aussie who complained about loosing 1 bar after 5k km he had a dodgy cell too can't remember what happened to him. Hi Gabzmiev, How does one do this? Or is it something that needs to be done by Nissan?
|
|
|
Post by Feng on Jul 14, 2015 14:01:17 GMT 11
What does cell #1 look like when the whole pack is fully charged? To balance the pack just charge it to 100% and leave it plugged in for up to four hours. Maybe do it for a few nights in a row for good measure?
Maybe using a quick charger might do something. Nothing to lose there if you try.
|
|
|
Post by organist on Jul 14, 2015 16:38:12 GMT 11
Hi feng. I noticed after three 100% charges that cell #1 was about only 4-5mV less than other cells, but the huge difference had returned by the time the battery was near Battery warning (and probably beforehand too).
|
|
|
Post by Feng on Jul 14, 2015 17:18:17 GMT 11
|
|
|
Post by organist on Jul 14, 2015 17:21:48 GMT 11
Thanks feng- have written directly to him too now.
|
|
|
Post by hieronymous on Jul 14, 2015 19:27:57 GMT 11
Purchased my NZ-new LEAF 5 weeks ago, and have since noticed a "Weak Cell #1" - around 15mV below the other 95 pairs when in a Low Battery Warning. Effectively the other 95 cells are being stopped from discharging fully, while Cell #1 is protected from dropping below a minimum level. The State Of Charge (LeafSpy) of the battery is showing 21% when the battery is almost in Turtle Mode. Anyone had any experience with Weak cells, and anyone had any experience with Nissan's attitude to such faults? Sadly, their standard tests don't seem to show a single weak cell, even if it ultimately affects the performance of the entire battery! Hi organist Commiserations for your weak HV battery pair; it's ironic that it is only because of your use of Leaf Spy that this is an issue for you, and that you presumably would otherwise have remained blissfully ignorant of this and been perfectly happy with your new car. My advice therefore, is to forget about the numbers and concentrate on whether your Leaf is doing everything you wanted. It's a battery world, but battery appliances have a short battery life, and sooner or later a replacement is required. The big question is whether your actual/intended usage for the foreseeable future is going to be affected in any practical way by a weak battery cell. So given calculated KWh is generally regarded as the best measure of usable energy in the battery, what numbers are you getting from a full charge (KWh, AHr, SOH), especially after battery balancing? What km's are you wanting to get from a single charge on a daily basis, and although you have had the Leaf only 5 weeks, are you having range issues? Nissan's track record on this is well known; if you have 12 bars then your battery is fine, and unless your weak cell throw a code, nothing is wrong. My suspicion is that battery manufacturing tolerances are quite variable, and consumers just don't know that their shiny new iPad perhaps has a crappy battery because tools like Leaf Spy are few and far between. it's my perception that driving conditions and driver choices have by far the biggest impact on range, and that, except for owners wanting maximum range, battery cell weakness isn't an practical issue. So unless you are one of those, relax and love your Leaf....
|
|
|
Post by organist on Jul 14, 2015 19:42:01 GMT 11
Hi hieronymous
I purchased Leafspy when I found I was not getting the expected range from my new LEAF - despite "positive" battery tests from Service Centres. I am not able to reach a nearby town 47km away and return. My intention for the LEAF was to undertake a journey (https://www.facebook.com/evtripnz) to show that EVs were a feasible choice for people to start considering now. At this time, I believe this weak cell is probably why I'm not going to manage To reach the expected ranges on the trip.
Today, I've driven 32km around town after an 80% charge last night. I've dropped from 9 bars down to 4 bars in that time.
The maximum I've ever put into the battery was 16.63kWh which was a 100% charge from the LEAF reporting it was nearly empty. This is nowhere near the 24kWh capacity expected.
LeafSpy has simply focused my attention on this one cell out of ninety-six pairs, which seems to having a significant effect of the reporting of battery remaining to the LEAF.
Yup, I love driving EVs but I don't want to spend the cost of a "new" car for one that's (been stored for 3 years and) only gives me 80% of the battery's capacity.
|
|
|
Post by hieronymous on Jul 14, 2015 20:56:42 GMT 11
Hi hieronymous I purchased Leafspy when I found I was not getting the expected range from my new LEAF - despite "positive" battery tests from Service Centres. I am not able to reach a nearby town 47km away and return. My intention for the LEAF was to undertake a journey (https://www.facebook.com/evtripnz) to show that EVs were a feasible choice for people to start considering now. At this time, I believe this weak cell is probably why I'm not going to manage To reach the expected ranges on the trip. Today, I've driven 32km around town after an 80% charge last night. I've dropped from 9 bars down to 4 bars in that time. The maximum I've ever put into the battery was 16.63kWh which was a 100% charge from the LEAF reporting it was nearly empty. This is nowhere near the 24kWh capacity expected. LeafSpy has simply focused my attention on this one cell out of ninety-six pairs, which seems to having a significant effect of the reporting of battery remaining to the LEAF. Yup, I love driving EVs but I don't want to spend the cost of a "new" car for one that's (been stored for 3 years and) only gives me 80% of the battery's capacity. Hi organist Then triple commiserations; I have a much clearer picture now of where your Leaf is at. My Leaf had a few 100% charges in the first 2 months of ownership; SOH was then 96%, AHr about 63.3, and the charge produced 20.2 KWh. Discussion on MNL suggests that 2011-12 Leafs never got more than 21.x KWh as newly manufactured vehicles. Ours of course were already 2+ years past that. I remember a thread on this forum last year where allegedly a Perth owner was so disgusted at losing a bar in 5? months he kicked up a public stink on Facebook, and Nissan Australia reportedly got straight back to him. I don't recall any more than that, but I fear you may need to be equally vocal to force Nissan to do something meaningful. So I'm thinking Fair Go, and if you possibly are a Consumer member, having a go at Nissan through Consumer via the Fair Trading Act or any other relevant consumer legislation. I was just reading a post on MNL where a 150mV min/max range was described as marginal, and yours is worse than that, and in a car sold as new that is completely unacceptable. You certainly should be able to do a 100km return trip on a 100% charge with conservative driving, even if it is winter. I hope you are able to find a way to get some satisfaction and significant improvement in your Leaf's range.
|
|
|
Post by organist on Jul 14, 2015 21:15:03 GMT 11
I am certainly interested in anyone else's experiences in Nissan's reaction to this problem. My "local" LEAF Technician is soon forwarding all my logs and info to Nissan NZ and I'm hoping they might see past the 5-star battery tests and look to replace one segment of my battery pack... Here's hoping anyhow...
|
|
|
Post by hieronymous on Jul 14, 2015 21:24:15 GMT 11
I am certainly interested in anyone else's experiences in Nissan's reaction to this problem. My "local" LEAF Technician is soon forwarding all my logs and info to Nissan NZ and I'm hoping they might see past the 5-star battery tests and look to replace one segment of my battery pack... Here's hoping anyhow... Hi organist I think the Perth Facebook car was here
|
|
|
Post by Cachexian (Gordon) on Jul 14, 2015 23:07:57 GMT 11
Doubtless the VLB warning kicks in early to prevent the weak cell from dropping to too low a voltage.
The cell voltage shouldn't be allowed to drop below 3.3V or it could be risky.
I had a similar thing happen to a cell on my ebike battery pack (which did not have any BMS let alone a sophisticate one like the leaf). The low cell caused an irretrievable drop in the voltage of the battery pack and puffed up. Unlike the Leaf, a singe cell couldn't be swapped out so the whole pack had to go to the recycler.
Hopefully Nissan will replace your cell.
|
|
reecho
EV Enthusiast
Posts: 39
|
Post by reecho on Jul 15, 2015 22:35:11 GMT 11
I'm not sure there will be any new stock of the gen 1 Leaf cells left to do any warranty work on them. They can't mix old and new type cells either.
|
|
|
Post by Cachexian (Gordon) on Jul 15, 2015 22:53:38 GMT 11
Why not? Are they a different form factor? Or different chemistry? I suppose that even though different chemistries will have the same nominal voltage, the discharge patterns would be different.. I will be very interested to hear Nissan's responses to this problem. Surely in this circumstance the buyer is protected under NZ Consumer Law. Nissan can't sell something that can't be serviced. (Presuming the law is similar to that in Oz)
|
|
reecho
EV Enthusiast
Posts: 39
|
Post by reecho on Jul 15, 2015 23:07:07 GMT 11
There is speculation that the battery chemistry had changed for 2013 models. This has never been confirmed by Nissan, but users worldwide have had less degradation for the similar distances travelled. I don't know about the form factor. There hasn't been a updated Leaf pack teardown that I have seen. There is a possibility that some early version cells are still available for swaps, maybe ex Japan. My last conversation with Nissan in Melbourne tended to indicate that was unlikely.
|
|
|
Post by philcanberra on Jul 17, 2015 17:49:19 GMT 11
so the self help would be to discharge and balance the pack several times. and see if the BMS can correct it. there was a aussie who complained about loosing 1 bar after 5k km he had a dodgy cell too can't remember what happened to him. I ALWAYS lose a bar every 4-5km until flat? I have a few dodgy cells 223mv lower than the rest, Nissan don't care and won't do anything, I've tried
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Jul 17, 2015 20:15:20 GMT 11
cell 17 out of 88 low for me in 2011 imiev most noticeable when down to 3/16 bars
|
|
|
Post by dimaivanov on Jul 22, 2015 17:46:13 GMT 11
Hey Organist, I'm Dima. Just bought a leaf in Auckland over the weekend. Can you tell me - which ELM327 Bluetooth adapter thing did you buy? I got one off TradeMe, but Leafspy told me it's a 2.1 and not the 1.5 as was advertised on TradeMe. So now I need to purchase another one, and hopefully this time I'll get the right one - if you can advice, that'd be great. Cheers, Dima
|
|
|
Post by hieronymous on Jul 22, 2015 20:13:16 GMT 11
Hi Dima Have you tried to use your 2.1? My ipad version of Leafspy reports my adapter is 2.1 and it works just fine....
|
|
|
Post by organist on Jul 25, 2015 7:36:04 GMT 11
Hi Dima The product I bought was off Amazon and I got given a link to it and bought it from that link - didn't notice its specifications . There are much better people on this board to advise you! All I can see now there is some ELM327, which is not what I bought. Martin
|
|
|
Post by quaternary on Jul 27, 2015 21:19:00 GMT 11
Hey Organist, I'm Dima. Just bought a leaf in Auckland over the weekend. Can you tell me - which ELM327 Bluetooth adapter thing did you buy? I got one off TradeMe, but Leafspy told me it's a 2.1 and not the 1.5 as was advertised on TradeMe. So now I need to purchase another one, and hopefully this time I'll get the right one - if you can advice, that'd be great. Cheers, Dima Hi Dima, Hope you're enjoying your Leaf. It made a big difference to my 'range anxiety' having bought a dongle and using it with LeafSpy/LeafStat, and getting some hard data. There is another thread here: ozleaf.proboards.com/thread/565/question-battery-percentage-2012-leafwith a discussion and links to some of the various OBD dongles people have bought (bluetooth ones for Android; Wifi ones for iPhone). You'll be able to see the one I bought, for example, but it's a Wifi based one for an iPhone, which won't be helpful for you if your device is Android. One idea is to email Jim the author of LeafSpy with the make and model and a photo of the dongle you have, and see if he'd expect it to be working with LeafSpy. (His email address is on the Google app store). Cheers Mark
|
|
|
Post by hieronymous on Jul 27, 2015 22:11:03 GMT 11
You can get bluetooth adapters for the Leaf which are android only, but you can also get wifi adapters which work with both android and iPad/iPhone; I have one of each as I rely on Leafspy for daily charging, and can use my iPad or Samsung S3. The main thing to look for in an Elm327 adapter is that it needs to be able to read CAN bus protocols.
|
|
|
Post by organist on Dec 16, 2015 11:44:33 GMT 11
Whereas my tests under Low Battery conditions show a 216mV, Nissan NZ did tests and came up with nothing more than 50mV, therefore not replacing. Personally, I think they must have tested under charged battery conditions.
|
|
|
Post by rusdy on Dec 16, 2015 12:49:14 GMT 11
Whereas my tests under Low Battery conditions show a 216mV, Nissan NZ did tests and came up with nothing more than 50mV, therefore not replacing. Personally, I think they must have tested under charged battery conditions. Hmmm... interesting. So far, only user 'РБМК' had luck to get Nissan to replace the weak cell. Even user 'philcanberra' looks like have the same problem (and Nissan refuse to replace). Looking at your LeafSpy, with SOH > 90% but can't make 47km return trip is poor indeed. Even my leaf with SOH 85% can make 45km return trip in highway condition (100kph most of the time). Do note, Leaf only have a fraction of practical kWh usable. For example, mine, with SOH of 85%, only can use 70% of it as well before the low batt warning comes up (not turtle yet). This translates to: (24kWh)(85%)(70%) = 14.3kWh. This, only translates to 95km at 0.15kWh/km (mostly highway). If I measure the kWh at charging input, I would put in around 17kWh (which close to your figure above), considering charger and Lithium round trip efficiency (around 80%, don't have the reference handy at the moment). Quick charger is more efficient by the way (strange isn't it?). I got the figure of 70% from my experience to date. Fully charged (not 80% limit), brings the SoC to 90-92%. When the low batt warning comes up, it's around 20% (although I'm sure I can travel more, haven't tried this yet). So, my usable SoC only between 20 to 90%. The low batt warning at around 20% is a good idea me think. And the 90% absolute top limit, my guess, is due to the older chemistry limitation (high SoC at heat is really, really bad for the battery). In short, maybe you can plead your cases to Nissan, stating user 'РБМК' claim success?
|
|
|
Post by quaternary on Dec 16, 2015 15:01:08 GMT 11
Whereas my tests under Low Battery conditions show a 216mV, Nissan NZ did tests and came up with nothing more than 50mV, therefore not replacing. Personally, I think they must have tested under charged battery conditions. Hey Martin, do you know want we need to do. Let's charge our cars up fully, and drive in convoy somewhere, ie under identical speeds and environmental conditions, and then if we can show Nissan how poorly yours performs compared to ours (and our car shows no weak cells under low voltage conditions, and plus is the same year of manufacture / same spec [and colour - and god knows that always makes a difference!]) then how can they ignore the results - especially if one car performs particularly poorer than another. What do you think? Cheers Mark
|
|
|
Post by organist on Dec 16, 2015 15:06:20 GMT 11
I think that's a fantastic idea, Mark! Apart from - who would pay for the tow truck to collect mine? (Maybe you'd like to join me on evtrip.nz )
|
|
|
Post by quaternary on Dec 16, 2015 15:45:22 GMT 11
What we could do is when you get to Christchurch we fully charged up and then drive around a circult on the periphery of town and drive to turtle. And then we'll have the beloved in the "rescue vehicle" containing an AC generator, so that we can charge up enough to get home. We might even be able to get a few others to join in on the fun.
|
|