LDC strategy for charging 12v ACID Auxiliary battery.

Kia Soul EV Forum

Help Support Kia Soul EV Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

SoulEV2016

Well-known member
Joined
Jul 18, 2016
Messages
572
This graphic is made with :

- Soul EV mid-2016 car
- Torque Pro
- Values from the DC-DC converter (400v DC to 12v DC)

----

Probable Problem when you try to save energy = 12v ACID is not maintained at 14,0v-14,3v during the drive.
save energy = lights and climate are OFF + small travel + heated seat and steering wheel.

It's ok during the charge (14v) ... but if you use the 6,6 kW max power, the charge is quick and the ACID battery can not be charged at this fast rate (slow charge needed, constant voltage).

GrtrKH.png


Solution for KIA is to accelerate the "storage process" that it check the 12v Auxiliary battery.

But for this, you must leave the charge cable plugged to the car 24h/24.
Regulary charge of the ACID battery happen 1-3 times over 24h when the charge cable is always plugged.
 
Measure after a trip with stabilized inside temperature :

luWMqK.png


eaZycO.png


And when you enable the night light, the voltage raise at a charge level for the ACID 12v battery.

PdCAs2.png
 
Test of the ACID 12v Battery after 1 year and 10 000km.
No problem.

esyOLG.png


Same test made at -2°C (8000km) and now (19°C).
Variation on the 12v lines are the regulation of heated elements.
 
SoulEV2016 said:
Someone have access to the spec. of the LDC output power ?
(like 1500w max for 1 hour).

This question has never been properly answered.
I just did a test on my car. Drive mode: all lights on, seat heaters on, fans on max, wipers on, radio on high, mood lighting.



The efficiency of the LDC (Low Voltage DC-DC Converter) is about 55% if these numbers are right.
(Some of the Battery Current from the main battery may be going elsewhere, so efficiency may be better, but my guess is this is correct)
 
Back
Top