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Summary of 12V Battery Chatter

15K views 57 replies 23 participants last post by  Hitstirrer  
#1 · (Edited)
Updated

Thought to summarize the discussions on 12 V battery drainage. Please point out mistakes.
  • the 12 V battery is lower capacity than expected in a similar size class ICE because it doesn’t have to crank an engine. This means it is more susceptible to being drained and fatally damaged
  • The 12 V is a 60 Ah battery. However, common advice for lead acid batteries is not have them prolonged below 50% of charge capacity so to be very cautious, the effective total power delivery (capacity) is 30 Ah whereas a similar size ICE would have a 45 Ah capacity. That's a third less power capacity than we are used to with an ICE.
  • the I5 wakes and uses the 12 V when sending Bluelink notifications, doors open and plugged-in accessories communicate with it (e.g., wireless AirPlay devices trying to communicate with phones). This uses the 12 V.
  • Using Accessories mode drains the 12 V battery. Use Utility mode which uses the traction battery if prolonged use of radio and other conveniences is needed. It can be challenging to know if in Accessories or Utility mode.
  • Some third-party applications that use Bluelink can cause excessive waking of the car and drain the battery.
  • Some think shipping cars for a long time across oceans resulted in battery draw and damage to the 12 V.
  • the traction battery recharges the 12 V if the SOC is greater than 35% and the battery voltage approaches 12.1 V. It would be better if charging occurred at 12.3 V than so low to critical. The car tries 10 times to lift voltage and then stops until reset when the car is driven. One poster notes their car charges when below 35 % SOC.
  • the 12 V won’t recharge with the lift gate open
  • the front USB powers for longer when the car is off than other ports and accessories plugged into it will use power
  • The 12 V sockets do not provide power when the car is off
  • Some OBD scanners will draw power while the car is off, the same goes for battery monitors if they draw power while the car is off. We love our tech devices but they use power
  • lights left on will draw power
  • operating the power lift gate more than 5 times with the car off is a huge power draw
  • 12 V won’t charge with lift gate or hood open
  • having the car in Accessories mode is a major power draw
  • there are some reports of parasitic power drain by the head unit and charging door
  • a portable charge that many use is a NOCO GB40
  • The 12 V battery will be damaged if the charge is 12 V or less. This is why the car charges the battery when approaching 12.1 V
  • if a battery is drained very low it can be fatally damaged, especially in freezing conditions. A battery load test is recommended to insure continuing drain issues aren’t because of damage

Bottom line when not driving
  • there is less power capacity (about 1/3 less) in the 12 V than we expect from a similar ICE
  • it’s easier therefore to draw the charge down to damage the battery
  • limit the use of Accessories mode
  • For caution, keep SOC above 35%
  • remove any plugged-in accessories from USB, data port and battery
  • limit the need for the car to send Bluelink notifications when off (e.g., unlocked door notifications)
  • eliminate third-party application use of Bluelink
  • have all doors, hood and lift gate closed
  • have all lights off
  • limit occasions car wakes up such as walking by with FOB in pocket or using Bluelink
  • load test battery if voltage has fallen repeatedly below 12 V or a concern it doesn’t hold a charge
  • if all above doesn’t work then bring in for servicing
please suggest additions or changes and the IoniqPedia5 will be updated. Thanks.
 
#3 ·
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#9 ·
#10 · (Edited)
Not up to date. See the discussion starter or latest update post below for the current summary.

Thought to summarize the discussions on 12 V battery drainage. Please point out mistakes.
  • the 12 V battery is lower capacity than expected in a similar size class ICE because it doesn’t have to crank an engine. This means it is more susceptible to being drained and fatally damaged
  • The 12 V is a 60 Ah battery. However only 50% of the charge is available from a lead acid battery so the effective total power delivery (capacity) is 30 Ah whereas a similar size ICE would have a 45 Ah capacity. That's a third less power capacity than we are used to with an ICE.
  • the I5 wakes and uses the 12 V when sending Bluelink notifications, doors open and plugged in accessories communicate with it (e.g., wireless Air Play devices trying to communicate with phones). This uses the 12 V.
  • Some think shipping of cars for a long time across oceans resulted in battery draw and damage to the 12 V.
  • the traction battery recharges the 12 V if the SOC is greater than 35% and the battery voltage approaches 12.1 V. It would be better if charging occurred at 12.3 V than so low to critical. Car tries 10 times to lift voltage and then stops until reset when car is driven. One poster notes their car charges when below 35 % SOC.
  • the 12 V won’t recharge with the lift gate open
  • the front USB powers for longer when car is off than other ports and accessories plugged in to it will use power
  • The 12 V sockets do not provide power when car is off
  • OBD scanners will draw power while car is off (please correct if wrong), unsure of battery monitors if they draw power while off. We love our tech devices but they use power
  • lights left on will draw power
  • operating power lift gate more than 5 times with car off is a huge power draw
  • having car in Accessories mode is a major power draw
  • there are some reports of parasitic power drain by the head unit and charging door
  • a portable charge that many use is a NOCO GB40
  • The 12 V battery will be damaged if the charge is 12 V or less. This is why the car charges the battery when approaching 12.1 V
  • if a battery is drained very low it can be fatally damaged, especially in freezing conditions. A battery load test is recommended to insure continuing drain issues aren’t because of damage

Bottom line when not driving
  • there is less power capacity (about 1/3 less) in the 12 V than we expect from a similar ICE
  • its easier therefore to draw the charge down to damage the battery
  • For caution, keep SOC above 35%
  • remove any plugged in accessories from from USB, data port and battery
  • limit need of car to send Bluelink notifications when off (e.g., lock doors)
  • have all doors and lift gate closed
  • have all lights off
  • limit occasions car wakes up such walking by with FOB in pocket
  • load test battery if a concern it doesn’t hold a charge
please suggest additions or changes and this and the IoniqPedia5 will be updated. Thanks.
 
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#12 ·
Updated

Thought to summarize the discussions on 12 V battery drainage. Please point out mistakes.
  • the 12 V battery is lower capacity than expected in a similar size class ICE because it doesn’t have to crank an engine. This means it is more susceptible to being drained.
  • the I5 wakes and uses the 12 V when sending Bluelink notifications, doors open and plugged in accessories communicate with it (e.g., wireless Air Play devices trying to communicate with phones). This uses the 12 V.
  • Some think shipping of cars for a long time across oceans resulted in battery draw and damage to the 12 V.
  • the traction battery recharges the 12 V if the SOC is greater than 35% and the battery voltage approaches 12.1 V. Car tries 10 times to lift voltage and then stops until reset when car is driven
  • the 12 V won’t recharge with the lift gate open
  • the front USB powers for longer when car is off than other ports and accessories plugged in to it will use power
  • The 12 V sockets do not provide power when car is off
  • OBD scanners will draw power while car is off (please correct if wrong), unsure of battery monitors if they draw power while off. We love our tech devices but they use power
  • lights left on will draw power
  • operating power lift gate more than 5 times with car off is a huge power draw
  • having car in Accessories mode is a major power draw
  • there are some reports of parasitic power drain by the head unit and charging door
  • if a battery is drained very low it can be damaged, especially in freezing conditions. A battery load test is recommended to insure continuing drain issues aren’t because of damage

Bottom line when not driving
  • keep SOC above 35%
  • remove any plugged in accessories from from USB, data port and battery
  • limit need of car to send Bluelink notifications when off (e.g., lock doors)
  • have all doors and lift gate closed
  • have all lights off
  • limit occasions car wakes up such walking by with FOB in pocket
  • load test battery if a concern it doesn’t hold a charge
please suggest additions or changes and this and the IoniqPedia5 will be updated. Thanks.
Fit a BM2!
 
#17 · (Edited)
>The 12 V is a 60 Ah (reserve capacity) battery @CCA 550A. However only 50% of the charge is available from a lead acid battery so the effective total power delivery (capacity) is 30 Ah whereas a similar size ICE would have a 45 Ah capacity. That's a third less power capacity than we are used to with an ICE.
Ampere Hours is not the reserve capacity (RC). RC is the amount of time (minutes) that a fully-charged battery can deliver 25 amps of power at 80°F before falling below 10.5 volts or 1.75 volts per cell. RC is 92 minutes for the 2022 stock aux battery (CMF60L-DIN, 37110-3X100). 60 Ah is the stored energy capacity of the battery.

Why is only "50% of the charge is available from a lead acid battery"? Nothing limits discharge of the aux battery. Typically, if all is well, the aux battery charges back up from 80% aux battery soc according to the recent diagram, however nothing limits discharge below that if the recharge cycle does not happen at 80% soc.

I like the idea of the summary posting, thank you for putting this together.
 
#20 · (Edited)
Ampere Hours is not the reserve capacity (RC). RC is the amount of time (minutes) that a fully-charged battery can deliver 25 amps of power at 80°F before falling below 10.5 volts or 1.75 volts per cell. RC is 92 minutes for the 2022 stock aux battery. 60 Ah is the stored energy capacity of the battery.

Why is only "50% of the charge is available from a lead acid battery"? Nothing limits discharge of the aux battery. Typically, if all is well, the aux battery charges back up from 80% aux battery soc according to the recent diagram, however nothing limits discharge below that if the recharge cycle does not happen at 80% soc.

I like the idea of the summary posting, thank you for putting this together.
Thanks for commenting. I'll remove the nonsense about reserve capacity. I'm just going off guidance from the net and from my work with remote off-grid power generation and storage systems. For lead-acid recommendation is to not go below 50% of charge capacity, and that will be above 12 V. If needing to provide more of the charge capacity of the battery and go below 12 V, then deep-cycle batteries are recommended.
 
#21 · (Edited)
Updated

Thought to summarize the discussions on 12 V battery drainage. Please point out mistakes.
  • the 12 V battery is lower capacity than expected in a similar size class ICE because it doesn’t have to crank an engine. This means it is more susceptible to being drained and fatally damaged
  • The 12 V is a 60 Ah battery. However, only 50% of the charge is available from a lead acid battery so the effective total power delivery (capacity) is 30 Ah whereas a similar size ICE would have a 45 Ah capacity. That's a third less power capacity than we are used to with an ICE.
  • the I5 wakes and uses the 12 V when sending Bluelink notifications, doors open and plugged-in accessories communicate with it (e.g., wireless AirPlay devices trying to communicate with phones). This uses the 12 V.
  • Using Accessories mode drains the 12 V battery. Use Utility mode which uses the traction battery if prolonged use of radio and other conveniences is needed. It can be challenging to know if in Accessories or Utility mode.
  • Some third-party applications that use Bluelink can cause excessive waking of the car and drain the battery.
  • Some think shipping cars for a long time across oceans resulted in battery draw and damage to the 12 V.
  • the traction battery recharges the 12 V if the SOC is greater than 35% and the battery voltage approaches 12.1 V. It would be better if charging occurred at 12.3 V than so low to critical. The car tries 10 times to lift voltage and then stops until reset when the car is driven. One poster notes their car charges when below 35 % SOC.
  • the 12 V won’t recharge with the lift gate open
  • the front USB powers for longer when the car is off than other ports and accessories plugged into it will use power
  • The 12 V sockets do not provide power when the car is off
  • Some OBD scanners will draw power while the car is off, the same goes for battery monitors if they draw power while the car is off. We love our tech devices but they use power
  • lights left on will draw power
  • operating the power lift gate more than 5 times with the car off is a huge power draw
  • having the car in Accessories mode is a major power draw
  • there are some reports of parasitic power drain by the head unit and charging door
  • a portable charge that many use is a NOCO GB40
  • The 12 V battery will be damaged if the charge is 12 V or less. This is why the car charges the battery when approaching 12.1 V
  • if a battery is drained very low it can be fatally damaged, especially in freezing conditions. A battery load test is recommended to insure continuing drain issues aren’t because of damage

Bottom line when not driving
  • there is less power capacity (about 1/3 less) in the 12 V than we expect from a similar ICE
  • it’s easier therefore to draw the charge down to damage the battery
  • limit the use of Accessories mode
  • For caution, keep SOC above 35%
  • remove any plugged-in accessories from USB, data port and battery
  • limit the need for the car to send Bluelink notifications when off (e.g., unlocked door notifications)
  • eliminate third-party application use of Bluelink
  • have all doors and lift gate closed
  • have all lights off
  • limit occasions car wakes up such as walking by with FOB in pocket or using Bluelink
  • load test battery if voltage has fallen repeatedly below 12 V or a concern it doesn’t hold a charge
  • if all above doesn’t work then bring in for servicing
please suggest additions or changes and the IoniqPedia5 will be updated. Thanks.
 
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#23 ·
As there are many reasons for a dead 12 V it is not model or year specific. I think awareness of the reasons will help lower the number of issues.
 
#24 ·
Just a quick note on OBD2 devices, since you invited comment.

Some cheaper ones do not switch off and can drain the 12V battery. But most, including some of the inexpensive ones, have a sleep function that shut down after a few minutes of zero activity (zero activity includes turning the car off). Make sure you read the spec when purchasing.
 
#26 · (Edited)
Updated
Thought to summarize the discussions on 12 V battery drainage. Please point out mistakes.
  • the 12 V battery is lower capacity than expected in a similar size class ICE because it doesn’t have to crank an engine. This means it is more susceptible to being drained and fatally damaged
  • The 12 V is a 60 Ah battery. However, only 50% of the charge is available from a lead acid battery so the effective total power delivery (capacity) is 30 Ah whereas a similar size ICE would have a 45 Ah capacity. That's a third less power capacity than we are used to with an ICE.
  • the I5 wakes and uses the 12 V when sending Bluelink notifications, doors open and plugged-in accessories communicate with it (e.g., wireless AirPlay devices trying to communicate with phones). This uses the 12 V.
  • Using Accessories mode drains the 12 V battery. Use Utility mode which uses the traction battery if prolonged use of radio and other conveniences is needed. It can be challenging to know if in Accessories or Utility mode.
  • Some third-party applications that use Bluelink can cause excessive waking of the car and drain the battery.
  • Some think shipping cars for a long time across oceans resulted in battery draw and damage to the 12 V.
  • the traction battery recharges the 12 V if the SOC is greater than 35% and the battery voltage approaches 12.1 V. It would be better if charging occurred at 12.3 V than so low to critical. The car tries 10 times to lift voltage and then stops until reset when the car is driven. One poster notes their car charges when below 35 % SOC.
  • the 12 V won’t recharge with the lift gate open
  • the front USB powers for longer when the car is off than other ports and accessories plugged into it will use power
  • The 12 V sockets do not provide power when the car is off
  • Some OBD scanners will draw power while the car is off, the same goes for battery monitors if they draw power while the car is off. We love our tech devices but they use power
  • lights left on will draw power
  • operating the power lift gate more than 5 times with the car off is a huge power draw
  • having the car in Accessories mode is a major power draw
  • there are some reports of parasitic power drain by the head unit and charging door
  • a portable charge that many use is a NOCO GB40
  • The 12 V battery will be damaged if the charge is 12 V or less. This is why the car charges the battery when approaching 12.1 V
  • if a battery is drained very low it can be fatally damaged, especially in freezing conditions. A battery load test is recommended to insure continuing drain issues aren’t because of damage

Bottom line when not driving
  • there is less power capacity (about 1/3 less) in the 12 V than we expect from a similar ICE
  • it’s easier therefore to draw the charge down to damage the battery
  • limit the use of Accessories mode
  • For caution, keep SOC above 35%
  • remove any plugged-in accessories from USB, data port and battery
  • limit the need for the car to send Bluelink notifications when off (e.g., unlocked door notifications)
  • eliminate third-party application use of Bluelink
  • have all doors and lift gate closed
  • have all lights off
  • limit occasions car wakes up such as walking by with FOB in pocket or using Bluelink
  • load test battery if voltage has fallen repeatedly below 12 V or a concern it doesn’t hold a charge
  • if all above doesn’t work then bring in for servicing
please suggest additions or changes and the IoniqPedia5 will be updated. Thanks.
 
#28 ·
Do we know if the rear seat power plug uses battery is something is plugged in and the car is locked? Seems like the red light stays on.

Also, I know it won't help with a parasitic draw, but sounds like a lithium 12v battery could eliminate some of these concerns.
I don't have the interior V2L but my understanding is the car needs to be in Utility mode when off for the V2L sockets to be powered. As for a Li 12 V., it can help prevent damage to the battery from being heavily drawn down in charge. If the Li 12 V has a higher capacity than the lead acid then that will help. Regardless of lead acid or Li, below a certain charge level, the car won't start regardless.
 
#29 · (Edited)
Updated

Thought to summarize the discussions on 12 V battery drainage. Please point out mistakes.
  • the 12 V battery is lower capacity than expected in a similar size class ICE because it doesn’t have to crank an engine. This means it is more susceptible to being drained and fatally damaged
  • The 12 V is a 60 Ah battery. However, common advice for lead acid batteries is not have them prolonged below 50% of charge capacity so to be very cautious, the effective total power delivery (capacity) is 30 Ah whereas a similar size ICE would have a 45 Ah capacity. That's a third less power capacity than we are used to with an ICE.
  • the I5 wakes and uses the 12 V when sending Bluelink notifications, doors open and plugged-in accessories communicate with it (e.g., wireless AirPlay devices trying to communicate with phones). This uses the 12 V.
  • Using Accessories mode drains the 12 V battery. Use Utility mode which uses the traction battery if prolonged use of radio and other conveniences is needed. It can be challenging to know if in Accessories or Utility mode.
  • Some third-party applications that use Bluelink can cause excessive waking of the car and drain the battery.
  • Some think shipping cars for a long time across oceans resulted in battery draw and damage to the 12 V.
  • the traction battery recharges the 12 V if the SOC is greater than 35% and the battery voltage approaches 12.1 V. It would be better if charging occurred at 12.3 V than so low to critical. The car tries 10 times to lift voltage and then stops until reset when the car is driven. One poster notes their car charges when below 35 % SOC.
  • the 12 V won’t recharge with the lift gate open
  • the front USB powers for longer when the car is off than other ports and accessories plugged into it will use power
  • The 12 V sockets do not provide power when the car is off
  • Some OBD scanners will draw power while the car is off, the same goes for battery monitors if they draw power while the car is off. We love our tech devices but they use power
  • lights left on will draw power
  • operating the power lift gate more than 5 times with the car off is a huge power draw
  • having the car in Accessories mode is a major power draw
  • there are some reports of parasitic power drain by the head unit and charging door
  • a portable charge that many use is a NOCO GB40
  • The 12 V battery will be damaged if the charge is 12 V or less. This is why the car charges the battery when approaching 12.1 V
  • if a battery is drained very low it can be fatally damaged, especially in freezing conditions. A battery load test is recommended to insure continuing drain issues aren’t because of damage

Bottom line when not driving
  • there is less power capacity (about 1/3 less) in the 12 V than we expect from a similar ICE
  • it’s easier therefore to draw the charge down to damage the battery
  • limit the use of Accessories mode
  • For caution, keep SOC above 35%
  • remove any plugged-in accessories from USB, data port and battery
  • limit the need for the car to send Bluelink notifications when off (e.g., unlocked door notifications)
  • eliminate third-party application use of Bluelink
  • have all doors and lift gate closed
  • have all lights off
  • limit occasions car wakes up such as walking by with FOB in pocket or using Bluelink
  • load test battery if voltage has fallen repeatedly below 12 V or a concern it doesn’t hold a charge
  • if all above doesn’t work then bring in for servicing
please suggest additions or changes and the IoniqPedia5 will be updated. Thanks.
 
#31 · (Edited)
> the traction battery recharges the 12 V if the SOC is greater than 35% and the battery voltage approaches 12.1 V. It would be better if charging occurred at 12.3 V than so low to critical. The car tries 10 times to lift voltage and then stops until reset when the car is driven. One poster notes their car charges when below 35 % SOC.

The 12 V battery will be damaged if the charge is 12 V or less. This is why the car charges the battery when approaching 12.1 V
IMHO This freaks people out for no reason. It is best to be above 12V for longest life, however a 12V battery can recover fine from as little as 11.6V with very minor changes if any. Many batteries can be restored as well.

Also, I think the 50% language should still be reworded. Perhaps add the quote of how you replied that this is based on your internet information, not on any I5 system information. I5 ignition off - cycles the aux battery between 80% to 92% soc up to 10 times, then there are no safeguards or limits before the next drive or charging session. There is no documented I5 program that has any relation to 50% soc. If you want to say in your opinion, always try to keep the aux battery above 50% soc, that is certainly appropriate I5 12V chatter.

Most BM2 curves that I have been reviewing support the recent chart, ignition off, start charge at 80%. The 2022 standard battery is a flooded lead acid battery, so I also think many of the reported conversion charts are not for our 2022 standard OEM 12V aux battery. Here is an example by @Restyler 12V Battery drain Notice that when I5 decides to charge the aux batt, the voltage immediately drops. This lower voltage is simply the momentary heavy load of starting systems including the LDC to charge the aux batt. For example, the decision to charge after 16:21 was made at 12.5V, then when systems came on, there was a momentary spike down to 12.2V or so. The downward spike was cuased by the earlier decision at 12.5V to start the aux battery charging, but the decision was made at 12.5V (probably the aux battery sensor reported about 85% soc).
Image
Image
 
#32 ·
Updated

Thought to summarize the discussions on 12 V battery drainage. Please point out mistakes.
  • the 12 V battery is lower capacity than expected in a similar size class ICE because it doesn’t have to crank an engine. This means it is more susceptible to being drained and fatally damaged
  • The 12 V is a 60 Ah battery. However, only 50% of the charge is available from a lead acid battery so the effective total power delivery (capacity) is 30 Ah whereas a similar size ICE would have a 45 Ah capacity. That's a third less power capacity than we are used to with an ICE.
  • the I5 wakes and uses the 12 V when sending Bluelink notifications, doors open and plugged-in accessories communicate with it (e.g., wireless AirPlay devices trying to communicate with phones). This uses the 12 V.
  • Using Accessories mode drains the 12 V battery. Use Utility mode which uses the traction battery if prolonged use of radio and other conveniences is needed. It can be challenging to know if in Accessories or Utility mode.
  • Some third-party applications that use Bluelink can cause excessive waking of the car and drain the battery.
  • Some think shipping cars for a long time across oceans resulted in battery draw and damage to the 12 V.
  • the traction battery recharges the 12 V if the SOC is greater than 35% and the battery voltage approaches 12.1 V. It would be better if charging occurred at 12.3 V than so low to critical. The car tries 10 times to lift voltage and then stops until reset when the car is driven. One poster notes their car charges when below 35 % SOC.
  • the 12 V won’t recharge with the lift gate open
  • the front USB powers for longer when the car is off than other ports and accessories plugged into it will use power
  • The 12 V sockets do not provide power when the car is off
  • Some OBD scanners will draw power while the car is off, the same goes for battery monitors if they draw power while the car is off. We love our tech devices but they use power
  • lights left on will draw power
  • operating the power lift gate more than 5 times with the car off is a huge power draw
  • having the car in Accessories mode is a major power draw
  • there are some reports of parasitic power drain by the head unit and charging door
  • a portable charge that many use is a NOCO GB40
  • The 12 V battery will be damaged if the charge is 12 V or less. This is why the car charges the battery when approaching 12.1 V
  • if a battery is drained very low it can be fatally damaged, especially in freezing conditions. A battery load test is recommended to insure continuing drain issues aren’t because of damage

Bottom line when not driving
  • there is less power capacity (about 1/3 less) in the 12 V than we expect from a similar ICE
  • it’s easier therefore to draw the charge down to damage the battery
  • limit the use of Accessories mode
  • For caution, keep SOC above 35%
  • remove any plugged-in accessories from USB, data port and battery
  • limit the need for the car to send Bluelink notifications when off (e.g., unlocked door notifications)
  • eliminate third-party application use of Bluelink
  • have all doors and lift gate closed
  • have all lights off
  • limit occasions car wakes up such as walking by with FOB in pocket or using Bluelink
  • load test battery if voltage has fallen repeatedly below 12 V or a concern it doesn’t hold a charge
  • if all above doesn’t work then bring in for servicing
please suggest additions or changes and the IoniqPedia5 will be updated. Thanks.
So this a great thread. I left my Limited in the garage from June to October 22 with an 80% charge. When I got back to it the charge was at 74% I think and no issues. I have not experienced a 12v failure but wonder if replacing the factory installed battery with something more robust is advisable or effective to reduce potential for issues.
 
#34 · (Edited)
Updated

Thought to summarize the discussions on 12 V battery drainage. Please point out mistakes.
  • the 12 V battery is lower capacity than expected in a similar size class ICE because it doesn’t have to crank an engine. This means it is more susceptible to being drained and fatally damaged
  • The 12 V is a 60 Ah battery. However, common advice for lead acid batteries is not have them prolonged below 50% of charge capacity so to be very cautious, the effective total power delivery (capacity) is 30 Ah whereas a similar size ICE would have a 45 Ah capacity. That's a third less power capacity than we are used to with an ICE.
  • the I5 wakes and uses the 12 V when sending Bluelink notifications, doors open and plugged-in accessories communicate with it (e.g., wireless AirPlay devices trying to communicate with phones). This uses the 12 V.
  • Using Accessories mode drains the 12 V battery. Use Utility mode which uses the traction battery if prolonged use of radio and other conveniences is needed. It can be challenging to know if in Accessories or Utility mode.
  • Some third-party applications that use Bluelink can cause excessive waking of the car and drain the battery.
  • Some think shipping cars for a long time across oceans resulted in battery draw and damage to the 12 V.
  • the traction battery recharges the 12 V if the SOC is greater than 35% and the battery voltage approaches 12.1 V. It would be better if charging occurred at 12.3 V than so low to critical. The car tries 10 times to lift voltage and then stops until reset when the car is driven. One poster notes their car charges when below 35 % SOC.
  • the 12 V won’t recharge with the lift gate open
  • the front USB powers for longer when the car is off than other ports and accessories plugged into it will use power
  • The 12 V sockets do not provide power when the car is off
  • Some OBD scanners will draw power while the car is off, the same goes for battery monitors if they draw power while the car is off. We love our tech devices but they use power
  • lights left on will draw power
  • operating the power lift gate more than 5 times with the car off is a huge power draw
  • 12 V won’t charge with lift gate or hood open
  • having the car in Accessories mode is a major power draw
  • there are some reports of parasitic power drain by the head unit and charging door
  • a portable charge that many use is a NOCO GB40
  • The 12 V battery will be damaged if the charge is 12 V or less. This is why the car charges the battery when approaching 12.1 V
  • if a battery is drained very low it can be fatally damaged, especially in freezing conditions. A battery load test is recommended to insure continuing drain issues aren’t because of damage

Bottom line when not driving
  • there is less power capacity (about 1/3 less) in the 12 V than we expect from a similar ICE
  • it’s easier therefore to draw the charge down to damage the battery
  • limit the use of Accessories mode
  • For caution, keep SOC above 35%
  • remove any plugged-in accessories from USB, data port and battery
  • limit the need for the car to send Bluelink notifications when off (e.g., unlocked door notifications)
  • eliminate third-party application use of Bluelink
  • have all doors, hood and lift gate closed
  • have all lights off
  • limit occasions car wakes up such as walking by with FOB in pocket or using Bluelink
  • load test battery if voltage has fallen repeatedly below 12 V or a concern it doesn’t hold a charge
  • if all above doesn’t work then bring in for servicing
please suggest additions or changes and the IoniqPedia5 will be updated. Thanks.
 
#36 ·
Updated

Thought to summarize the discussions on 12 V battery drainage. Please point out mistakes.
  • the 12 V battery is lower capacity than expected in a similar size class ICE because it doesn’t have to crank an engine. This means it is more susceptible to being drained and fatally damaged
  • The 12 V is a 60 Ah battery. However, common advice for lead acid batteries is not have them prolonged below 50% of charge capacity so to be very cautious, the effective total power delivery (capacity) is 30 Ah whereas a similar size ICE would have a 45 Ah capacity. That's a third less power capacity than we are used to with an ICE.
  • the I5 wakes and uses the 12 V when sending Bluelink notifications, doors open and plugged-in accessories communicate with it (e.g., wireless AirPlay devices trying to communicate with phones). This uses the 12 V.
  • Using Accessories mode drains the 12 V battery. Use Utility mode which uses the traction battery if prolonged use of radio and other conveniences is needed. It can be challenging to know if in Accessories or Utility mode.
  • Some third-party applications that use Bluelink can cause excessive waking of the car and drain the battery.
  • Some think shipping cars for a long time across oceans resulted in battery draw and damage to the 12 V.
  • the traction battery recharges the 12 V if the SOC is greater than 35% and the battery voltage approaches 12.1 V. It would be better if charging occurred at 12.3 V than so low to critical. The car tries 10 times to lift voltage and then stops until reset when the car is driven. One poster notes their car charges when below 35 % SOC.
  • the 12 V won’t recharge with the lift gate open
  • the front USB powers for longer when the car is off than other ports and accessories plugged into it will use power
  • The 12 V sockets do not provide power when the car is off
  • Some OBD scanners will draw power while the car is off, the same goes for battery monitors if they draw power while the car is off. We love our tech devices but they use power
  • lights left on will draw power
  • operating the power lift gate more than 5 times with the car off is a huge power draw
  • 12 V won’t charge with lift gate or hood open
  • having the car in Accessories mode is a major power draw
  • there are some reports of parasitic power drain by the head unit and charging door
  • a portable charge that many use is a NOCO GB40
  • The 12 V battery will be damaged if the charge is 12 V or less. This is why the car charges the battery when approaching 12.1 V
  • if a battery is drained very low it can be fatally damaged, especially in freezing conditions. A battery load test is recommended to insure continuing drain issues aren’t because of damage

Bottom line when not driving
  • there is less power capacity (about 1/3 less) in the 12 V than we expect from a similar ICE
  • it’s easier therefore to draw the charge down to damage the battery
  • limit the use of Accessories mode
  • For caution, keep SOC above 35%
  • remove any plugged-in accessories from USB, data port and battery
  • limit the need for the car to send Bluelink notifications when off (e.g., unlocked door notifications)
  • eliminate third-party application use of Bluelink
  • have all doors, hood and lift gate closed
  • have all lights off
  • limit occasions car wakes up such as walking by with FOB in pocket or using Bluelink
  • load test battery if voltage has fallen repeatedly below 12 V or a concern it doesn’t hold a charge
  • if all above doesn’t work then bring in for servicing
please suggest additions or changes and the IoniqPedia5 will be updated. Thanks.
 
#49 ·
In my findings and research, this is what I found (I'm based in the UK).

1. Hyundai cheaped out on the 12V lead acid battery.
2. The 12V battery does not charge if your main/ traction battery has lower than Approx 18% charge.
3. Possible issues connected with CCU, but unconfirmed. I just hope my car is not part of the bad batch from Korea with CCU issues.
4. The number of 3rd party apps thru’ Bluelink for data uploads to the cloud (another reason that Hyundai had provided earlier in Jan this year for the depleting 12v batt) can exceed thousands- some even recorded up to 5000 pings in a day, but Hyundai Engineering claim to have reduced this to 20 requests per day (TBC). I would be interested to dig deeper into the 3rd party apps that use Bluelink and see if there are GDPR laws flouted/ my data being sold / shared without authorization.
5. Battery management needs upgrades, the sleeping giant of a battery needs a fire starter and you’re out of flints- go figure.
6. Replacement of Lithium battery might invalidate warranty and could have issues with cold starts if you’re living where the temp drops below 0. This could be a viable alternative, but this isn’t a consumer decision.