Frozen Battery: BYD Seal LFP Charging Curve in Worst Case Scenario

Last night it was -10 °C here in Finland and my BYD Seal was sleeping outside without being plugged in, so in the morning after being stationary for some 15 hours, the car was frozen and the battery pretty much as well!
I decided to take the car right to a nearby DC charger without any significant driving distance before the charging session i.e. there was no time for the battery to heat up. This is the worst case scenario for charging: starting with freezing cold battery and going straight to DC charging. How did BYD's LFP battery handle this far from optimal charging condition and how was the charging curve? One thing is for sure, it wasn't the usual curve you see with the Seal!
I also had the latest car software installed, the v1.3.1 with which some users have been seeing some issues with DC charging specifically, so this charging curve test was also to see if the charging behavior is normal with this software version or is there something weird going on with it.
#byd #bydseal #electriccar #charging #ccs #chargingcurve #evchargers #evcharging #ev #electriccars #LFP #battery #evbattery #evbatteries

[@FlyingBirdFlip]

Ordered a BYD Seal Excellence, and seen all your videos in preparation, keep up the great work!

[@ElectricSeal-bq5wu]

Awesome! Thanks, and congrats on the car 😎

[@t.d.5804]

Hei ! Its not that cold over here in Germany. My BYD blade LFP (in a Tesla Model Y) only once had 0°C. After a 20min drive incl. auto preheating the battery charged with nearly 3C (3C=176kW is the limit). LFP ist not LFP, some chems are different and in the case of BYD they produce very good cells, but BYD cars lack the proper design around the cells for fast charging and preheating. Its not the cells alone which define a battery. The former CATL LFP used by Tesla are really poor. They need high temp (40°C) to fast charge and even at +10°C they suffer and reduce power, thats a cell problem. 2024 cells from BYD and CATL did improve a lot, currently LFP is the best choice for power/charging/cycles

[@ElectricSeal-bq5wu]

Thanks for sharing! Also next-gen LFP looks very promising for cold weather specifically, interesting to see how this tech keeps developing.

[@Twin.motors]

I've done supercharging tests in very cold temperatures ( -10c) with zero preheating, just drove to the supercharger which was 3km away and the car started charging straight away. ( CATL batteries LFP) I've heard the BYD is better but the CATL ones are also quite good.

[@ronnywe378]

There is no discrepancy from incar Display to the Charger display...the battery heating is on and this decreases the charging power. (40kW charger- 3kW heating=37kW car charging) Greating from Germany :D

[@ElectricSeal-bq5wu]

Makes sense! 👍

[@kepter9990]

Of course the limitations are purely from software. If the BMS allowed, you could charge at high power in low temperatures, but it would cause Lithium plating in the anode material and therefore damaging the battery. That's why BMS is limiting the chargin power in low temperatures.

[@ElectricSeal-bq5wu]

This is a good reminder that it is to protect the battery. Some BMSs may be less strict, but that could sacrifice SOH in the long run.

[@holetoanotheruniverse4690]

The start power of 9kw and the difference (Car - Charger) is also about 9kw. This is the Power of the Heating Elements

[@ElectricSeal-bq5wu]

Oh, is it as much as 9kw? I thought the heating/AC is more like 5-6kW. Interesting.

[@kepter9990]

I've got model 3 SR+ 2021 with LFP. I've done the same test. Keeping the car in -20 over night and then driving to DC charger 3km away. gettin 0kw to battery in sub 20% SoC. first 20 minutes it was just heating the battery. then Slowly ramping up. taking up to 40 minutes to reach 40kw charging power. With warm battery I can easily get 170kw at low SoC even in -20 celcius. But if you don't have time to heat up the battery, the charging power will be very very low. NMC batteries get much higher power in similar conditions.

[@ElectricSeal-bq5wu]

Thanks for sharing your experience. NMC chemistry is still ahead in this, but may not be for too long looking at the next-gen LFP tech - those things seem to reach high charging power even in -10 C

[@user-xi7wx9rf7x]

on an enyaq 80 with nmc battery you will get 90 kw even a -10 celsius without preheating but after drive on highway

[@kepter9990]

@@user-xi7wx9rf7x yes, this is true for any NMC-battery. Tesla model 3 LR has NMC battery and it will always get good charging performance. NMC cells need much less heating. Still any Tesla will get their peak power 170kw for LFP and 250kw for NMC in any weather and temperature if you pre-condition the battery. LFP has many other benefits over NMC. such as longevity, lasting up to double more cycles than NMC battery.

[@darahayes7190]

very interesting post , I recently used a brand new 400kw charger placed beside my normal 180kw unit and naturally I pluged into the new ultra high speed charger but was disgusted to only see 10kw and then the magic same figure of 8.5kw and it seemed to be stuck on this figure and having little or no patience I immediately cancelled and swaped over to the older 180kw unit where I immediately got 50 and ramped up quickly to 120 and completed my charge in a reasonable time , I arrived with only 10% and temp was above 10degs c car had only driven 8km from being left idle for 4 weeks (was overseas working) ... I do think you have identified a quirk with this new software version ,.. again thanks for great content. dara hayes

[@alphaomega1969]

The car is slow charching to expel cold temp which is fluid or liquid and it has to do it slow until safe to fast charge to avoid damaging the cells.

[@yw42a]

Well done

[@ElectricSeal-bq5wu]

Thanks!

[@林振华-t4v]

The navigation can make a bit different especially driving for 10 km. If you tell the car going to charging station, the battery thermal managment will start increasing output to warm up the battery. That will speed up the Charging

[@ElectricSeal-bq5wu]

Very good point, have you tested this by yourself?

[@林振华-t4v]

​@@ElectricSeal-bq5wunot the seal, cause we dont have it in Canada. But my model 3 will do this when I tell the car Im going to charge station. I only try the supercharge and tesla enpoint charge not 3rd party lv3 charge. But experience preheat ing the battery only work for lv3 charge. It doesnt kick in for end point charge which is LV2 with 6-7 KW. That says, the seal shall have similar feature build in sofware. So when you going to fast charge the car. It will pre heat the bettery to make sure you can get the max out from the session.

[@ElectricSeal-bq5wu]

@ thanks for sharing. Actually, now that Seal’s v1.3.1 has the charging integrated to navi and route planner, they could fairly easily support this same functionality. I don’t think it’s available yet, though. Would be a nice little improvement.

[@altayaltay.]

We are waiting for the range test (100% to % 5or safe limit) too . Winter conditions are quite good for this.

[@ElectricSeal-bq5wu]

Sure, I'll make a video about this. 👍 Now it's +8 C though...maybe wait for the cold temps

[@Sparky783]

It'd be interesting to see it from a low SOC, it was 49% when you started, also could you run car scanner or something so we can see the temperature of the battery.

[@ElectricSeal-bq5wu]

True, OBD scanner would be insightful tool in cases like this!

[@alphaomega1969]

BYD battery heat system is used by Tesla too.

[@davidolsson]

There's an issue with the software. When warm it lets the battery get to hot and the throttle it as low as 20-40%. I've seen it alot this summer and autumn/winter. The car can't keep up the cooling. 😢

[@ElectricSeal-bq5wu]

It might also be partly due to the fact that the Seal’s battery cooling/heating uses the AC system instead of dedicated cooling system..someone who knows better can correct me if wrong.

[@kirodrix]

​@@ElectricSeal-bq5wu Not really, the seal has a dedicated cooling/heating for the battery but only on the top of it where Tesla have cooling/heating system at top AND bottom for the BYD LFP battery. The main problem is we didn't have any possibility to launch this system before the charge and that make a lot of difference than Tesla. Also, a weird point is the Seal U have a battery preconditioning option in the app ! That's completely crazy because the Seal U is strictly the same as the Seal but in SUV mode 😅

[@ElectricSeal-bq5wu]

@@kirodrix Interesting, thanks for sharing! Now this heating/cooling on top of the battery only could explain why there seems to be quite a bit of gap between the minimum and maximum battery cell temperature in the Seal (I've lately been checking this with OBD reader) and that is of course not optimal for charging.. But is it really a dedicated cooling/heating - I thought it utilizes the A/C system and the same heat pump which is used for the cabin as well? Also the Seal U having the preconditioning in the app is useful insight! This gives us hope to get the exact same option for the Seal as well.

[@hameedchishti3114]

greetings from Espoo. since start of cold weather, my seal's breaks on low speed has started to give annoying noise. have you noticed something similar?

[@ElectricSeal-bq5wu]

Yep, this is a common issue in colder weather, apparently some material choice. The breaks are very powerful and effective, which is great, but the sound on squeekyness is definitely less great. Warming up the brakes helps.

[@davidolsson]

This is embarrassing as BYD is making the battery and the bms.

[@ElectricSeal-bq5wu]

They should indeed be well positioned to integrate these technologies.

[@janvanrookhuijzen8309]

​@@ElectricSeal-bq5wu i think its pretty fine. You constructed a situation for a test that is not something you would in real life. BYD is probably protecting the battery this way against extra degradation due to high power in combination with low cell temp. It's using the power to heat up the battery first and ramps up charging as it heats up.

[@ElectricSeal-bq5wu]

@ You are right, this was really the worst case scenario to see what happens. Very rarely you need to go right away to charger with this cold battery in real life.

[@jean-michelrchdf6139]

Je pensais que le preconditionnement ne servait à rien. Maintenant j’ai la preuve que c’était une erreur. Merci.

[@ElectricSeal-bq5wu]

Yes, I do think preconditioning would have been of use here, maybe saving some 10-15min of charging time.

[@Chriztof]

Oui, l'idée serait de reproduire le même scénario en mettant le supercharger en destination pour voir : - si le pré-conditionnement se met en route - ce que ça change pour la courbe de charge... 😊 @ElectricSeal , je pense qu'il y aura d'autres matins givrés comme celui-ci..😊 Merci en tous cas pour ta chaîne 👍🏻 elle est à la fois pleine d'infos et fun en même temps. J'avais une EV6 pendant plus d'un an et après un passage en thermique, je vais revenir au VE. J'ai essayé la Seal RWD et la Seallion... Je pense que c'est cette dernière que je vais prendre, bien que j'adore la ligne de la Seal..🤩🫶🏻

[@jean-michelrchdf6139]

Il n’y a pas de preconditionnement sur la Seal.

[@davidolsson]

The seal cannot precon ..very strange that the nav or the driver cannot trigger this before arriving. The software is the thing that brings this car down. The hardware of the car is good but fw/sw is not good.

[@kirodrix]

@@davidolsson Seal U have the option to precon in app and a Seal U is a Seal but in a SUV mode. I'm not sure the Seal will never have a precon because the battery has a cooling/heating system at the top of it. Tesla decide to setup the heating/cooling at the top AND the bottom of the BYD LFP battery and also have precon so that help a lot. Maybe if BYD implement a precon it will help in cold temperature

[@b.b.2506]

How can anyone believe that the battery can charge quickly in winter at cold temperatures?

[@ElectricSeal-bq5wu]

I guess no one expects that, but it is still interesting to measure the charging curves in this quite extreme case, because it does vary a lot by car.

[@Yucior]

Can you share what is real / shown range of Seal in this conditions while at 80% battery? Thank you!

[@ElectricSeal-bq5wu]

I'll try to make a range test video in cold temps. Though right now it's +8 C again

[@jamesvandamme7786]

Hold your camera steady, please. I got dizzy trying to watch it.

[@ElectricSeal-bq5wu]

Thanks, will do 👌

[@cowkmetyiu]

feel sorry for the owner's decision on choosing BYD Seal BEV over any other proper solution. 😅 indeed not many consumers have the enough knowledge and information, and not understanding that BYD is in fact not famous for, or well-known for, or making good BEV solutions. Its major marketing is good at promoting New Energy Vehicles, including both PHEV and BEV. Well then, good at promoting its BEV. However after all, what BYD really does most is HEV and PHEV. 😂😂😂😂😂😂 BYD has been always trying very best at labelling their sales as NEV, for branding-up, promoting, marketing, selling their BEV under the NEV strategy, like scams but it works very well across the globe, especially in Western Europe 😢 To buy a chinese cheap deal BEV, I would rather suggest Europeans considering MG manufactured by SAIC, or Zeekr by Geely. Yet, there are still many other better Chinese options than BYD BEV. 😂 just my two cents.

[@ElectricSeal-bq5wu]

I think the Seal is pretty awesome 🤩 Very happy with it after 8 months of ownership.