Hyundai Ioniq 5 Battery
We've heard the stories and read the accounts about the low voltage (aka 12V) batteries in the Hyundai Ioniq 5 and they sound very familiar to us. Not because we've heard so many stories specifically about the Ioniq, but because we've heard so many in general about so many late model vehicles. Many of the stories have common threads- the car was sitting for a few days or a few weeks, there was no mention of an attempt to measure battery voltage or to charge the 12V battery.
One of the emerging trends we see with hybrids and EVs regarding their 12V batteries is a general lack of information about the voltage level of that battery or the mistaken belief that a 12-volt battery is at 100% state of charge, if it measures 12.0 volts. The reality is that a 12-volt battery that measures 12.0 volts can be more than 50% discharged. For some, that's because plugging in an EV doesn't guarantee that a discharged 12-volt battery will be recovered.
Some vehicles only operate the DC to DC converter under specific conditions. Others will periodically maintain the 12-volt battery, even when the vehicle is parked. If the 12-volt battery becomes deeply discharged, the vehicle may not be able to activate the contactors or control modules need to initiate high-voltage charging. A weak or internally damaged 12-volt battery may not recover, even if charging voltage is available.
Some hybrids and EVs have significant key-off loads from apps or accessories that might deeply discharge a 12-volt battery, like a wired dashcam on constant power. At the end of the day, a battery is essentially a box of energy, not a perpetual energy machine. If your Hyundai sits for extended periods of time and/or doesn't get driven or charged in a manner that is suitable for maintaining proper voltage in a 12-volt battery (at least 12.6V), it's possible the 12-volt battery can become deeply discharged.
If that happens often enough and/or the battery is left in a deeply discharged state for long enough, it may need to be replaced. When we see this type of issue with an ICE vehicle, we typically recommend buying and regularly using a quality battery charger or maintainer. The cadence we recommend is starting with a monthly charge. Chargers like OPTIMA chargers, will indicate battery voltage, so if you notice your battery is deeply discharged, it may need more frequent charging. If it is generally holding voltage, that cadence could be expanded.
However, in the case of a hybrid or EV owner, we might instead recommend purchasing a simple voltmeter. They can be had at many retailers for about $10 and are simple to use. If you don't know how, there are hundreds of YouTube videos that explain how to use a voltmeter. Measure the voltage of your 12-volt battery and if you find it is low, plug your car in and charge it. Then, check the voltage again after charging, to make sure the battery was charged.
If the battery doesn't measure at least 12.6V, you may want to disconnect the negative cable, let the vehicle sit for about 10 minutes and then attempt to fully charge the 12-volt battery with a standalone 12V battery charger. If the battery accepts a charge from the standalone battery charger, but not from the vehicle's charging system, there could be an issue with that system. If the battery voltage doesn't go up with a standalone battery charger, there could be an issue with the 12V battery.
If that's the case, you can take that battery to a quality auto parts retailer and have them load test the battery. Many auto parts retailers will offer this service for free. If you need a replacement battery, OPTIMA does offer a direct-fit upgrade with our DH5 YELLOWTOP. It comes with a three-year free replacement warranty, but if you purchase it directly from OPTIMA and buy an OPTIMA D1200+ battery charger at the same time, we'll add an additional year of free replacement warranty coverage to your OPTIMA battery
One of the emerging trends we see with hybrids and EVs regarding their 12V batteries is a general lack of information about the voltage level of that battery or the mistaken belief that a 12-volt battery is at 100% state of charge, if it measures 12.0 volts. The reality is that a 12-volt battery that measures 12.0 volts can be more than 50% discharged. For some, that's because plugging in an EV doesn't guarantee that a discharged 12-volt battery will be recovered.
Some vehicles only operate the DC to DC converter under specific conditions. Others will periodically maintain the 12-volt battery, even when the vehicle is parked. If the 12-volt battery becomes deeply discharged, the vehicle may not be able to activate the contactors or control modules need to initiate high-voltage charging. A weak or internally damaged 12-volt battery may not recover, even if charging voltage is available.
Some hybrids and EVs have significant key-off loads from apps or accessories that might deeply discharge a 12-volt battery, like a wired dashcam on constant power. At the end of the day, a battery is essentially a box of energy, not a perpetual energy machine. If your Hyundai sits for extended periods of time and/or doesn't get driven or charged in a manner that is suitable for maintaining proper voltage in a 12-volt battery (at least 12.6V), it's possible the 12-volt battery can become deeply discharged.
If that happens often enough and/or the battery is left in a deeply discharged state for long enough, it may need to be replaced. When we see this type of issue with an ICE vehicle, we typically recommend buying and regularly using a quality battery charger or maintainer. The cadence we recommend is starting with a monthly charge. Chargers like OPTIMA chargers, will indicate battery voltage, so if you notice your battery is deeply discharged, it may need more frequent charging. If it is generally holding voltage, that cadence could be expanded.
However, in the case of a hybrid or EV owner, we might instead recommend purchasing a simple voltmeter. They can be had at many retailers for about $10 and are simple to use. If you don't know how, there are hundreds of YouTube videos that explain how to use a voltmeter. Measure the voltage of your 12-volt battery and if you find it is low, plug your car in and charge it. Then, check the voltage again after charging, to make sure the battery was charged.
If the battery doesn't measure at least 12.6V, you may want to disconnect the negative cable, let the vehicle sit for about 10 minutes and then attempt to fully charge the 12-volt battery with a standalone 12V battery charger. If the battery accepts a charge from the standalone battery charger, but not from the vehicle's charging system, there could be an issue with that system. If the battery voltage doesn't go up with a standalone battery charger, there could be an issue with the 12V battery.
If that's the case, you can take that battery to a quality auto parts retailer and have them load test the battery. Many auto parts retailers will offer this service for free. If you need a replacement battery, OPTIMA does offer a direct-fit upgrade with our DH5 YELLOWTOP. It comes with a three-year free replacement warranty, but if you purchase it directly from OPTIMA and buy an OPTIMA D1200+ battery charger at the same time, we'll add an additional year of free replacement warranty coverage to your OPTIMA battery
