Is there a better 12V Battery for the BYD Atto 3?
Вставка
- Опубліковано 5 сер 2024
- A look at the charging parameters for the Atto 3 12V battery
#BYD #Atto 3 #12voltbatterycharger
New supply of high quality BYD Atto 3 parts at very competitive prices in Sydney Australia.
Visit my online shop
evpartz.online
![ЛЕБЕДЕВ у ДУДЯ: муху не обманешь 😁 [Пародия]](http://i.ytimg.com/vi/E74h5fvVrqs/mqdefault.jpg)
Good outcome.
Just a few points about the battery gauge you are using and LFP batteries. LFP battery cells have a very flat charge/discharge curve and voltage cannot be accurately used to determine the capacity. My figures will talk about individual cell voltages (there are 4 cells in a 12v battery). A full (100%) cell is around or just over 10:14 3.55v (some will say 3.6v) and when charge is stopped it will quickly settle to just under 3.4v. At about 95%, the cells are at around 3.25v. At about 50%, the cells are at around 3.2v. At about 30%, around 3.1v. The voltage is now going to fall quickly, particularly below 3.0v.
Unlike Lead Acid batteries, LFP batteries do not have a straight lineal charge/discharge curve (straight line on a graph). Hence the voltage can’t be used to accurately determine capacity. I’d say, you need to ignore the capacities reported by the Bluetooth device. Use it to for voltage and battery health, but not capacity and realise the capacity reported will be inaccurate.
Also, an LFP battery of this type has its own internal BMS to control cell charging and balancing and doesn’t rely on the vehicle charge to control the battery charging. All the vehicle does is deliver amps at a given voltage to the BMS and the BMS 10:14 charges the cells. The voltage of the vehicle charging system never reaches higher than 13.8v (I’ve seen reports of 13.9v), so the battery BMS will never see a voltage high enough to get to 100% state of charge (14.2-14.6v is required, depending on the BMS). Hence, the LFP battery doesn’t reach 100% and never finishes balancing the individual cells. That’s not a great drama, but it needs to be realised. Personally I would use a battery charger with a suitable lithium charge voltage to bring the battery to 100% every 3-6 months and let the BMS do its thing.
Hopefully the Seal and Dolphin charge voltage is suited to the LFP batteries that are fitted to them. The batteries are referred to in the manuals as Iron batteries or Iron starter batteries. There is even a mention in the manuals of a “wake up” procedure if the battery goes to sleep. One thing for sure is that the internal BMS will cut off the battery to discharge if the voltage of the cells goes into a low voltage, another neat trick of the BMS of 12v LFP batteries to protect the cells.
Thank you for the good information.
I have had no battery problems at all we ith the lead acid original.
It should be possible to replace it with a LiFePO four cell (4S) battery as long as it has its own BMS.
4S LiFePO batteries normally have a full charge floating point of 14.7V. It will probably work OK at 13.8V, but you would only get about 80% of the rated capability.
Hi Chris
Thank you for the great videos!
I'm definitely replacing the aux battery with similar LFP on my Atto 3 when it goes. What make/model did you get and where did you buy it?
Thank you!
Hi Marcus, Thank you for the feedback. It really motivates me to keep going.
I am importing these batteries at $199 pick up in Sydney or $215 delivered. Contact me if you want one.
@@CarnormousHow can I contact you?
Yeah the standard type 2 cable doesn't work because the pins aren't long enough to connect physically on the socket side.
What lifepo4 battery did purchase 🙂
Hi Alex, i imported some which are the same size as the old battery.
Please contact me if you are interested. Thanks.
@@Carnormous Hi Chris, ? what Amps did you go with e.g. 50 or 100 amps
Hey mate, I am keen on the battery, can you please send me the details?
Hi Kash, please send me an email for more battery details: 1907chris@gmail.com
And - as I suspected EV extension cables are not approved by the IEC - here's the blurb
"EV Charging Cables Extensions
Unfortunately the International Electrotechnical Commission (IEC) standard is clear on the matter; “A cord extension set or second cable assembly shall not be used in addition to the cable assembly for the connection of the EV to EVSE.”. Therefore any EV extension cable will sit outside of the standards and will affect your vehicle warranty in the event of a claim.
You therefore have 2 options when looking to extend your cable:
Extending Standard Untethered (Plug to Plug) Cables: Purchase a Type 1 or Type 2 cable for the full length you require and use your existing cable as a spare.
Extending Tethered Charge Point Cables: Purchase a Type 1 Tethered Cable or Type 2 Tethered Cable for the full length you require and replace your existing cable. "
I realise this doesn't solve your public charge point dilemma but the fact that the extension cable could void your warranty is a problem and the energy it's shedding would all be as heat and that could also be a problem.
Thanks for doing my research for me.