10-16-2024, 07:26 AM
A dc to dc charger is not just an isolator.
It will raise, or lower the vehicle system voltage to levels which will charge depleted house batteries faster.
Modern vehicles do not just seek to hold 14.2v, but will raise.or lower the voltage depending on how it can best affect miles per gallon.
This strategy can boost MPG by a small amount, but is absolutely horrible for a 50% charged battery that needs to get to as high a state of charge as possible while the engine is running.
With Lithium house baTteries, the vehicle votage can spike to over 15v in some situations, which would trigger the high voltage disconnect in the BMS, and this abrupt shutoff can cause transient voltage spikes which have the abiliy to fry electrical components instantly, or cumulatively over time.
On an older vehicle with simple voltage fixed regulation a dc to dc charger can be unnecessary or of little benefit, and potwntially even a detraction of efficacy
On a newer vehicle, it might be the only way to have the alternator actually feed the depleted house battery any signicant current.
It will raise, or lower the vehicle system voltage to levels which will charge depleted house batteries faster.
Modern vehicles do not just seek to hold 14.2v, but will raise.or lower the voltage depending on how it can best affect miles per gallon.
This strategy can boost MPG by a small amount, but is absolutely horrible for a 50% charged battery that needs to get to as high a state of charge as possible while the engine is running.
With Lithium house baTteries, the vehicle votage can spike to over 15v in some situations, which would trigger the high voltage disconnect in the BMS, and this abrupt shutoff can cause transient voltage spikes which have the abiliy to fry electrical components instantly, or cumulatively over time.
On an older vehicle with simple voltage fixed regulation a dc to dc charger can be unnecessary or of little benefit, and potwntially even a detraction of efficacy
On a newer vehicle, it might be the only way to have the alternator actually feed the depleted house battery any signicant current.
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