Hello! I have a special question to the forum. 3 months ago I switched from a Prius 2nd generation (drove it for 8 years) to a Prius v. According to this video the inverter from the Prius 2 constantly charges the 12 V battery AND provides 12 V to the Prius accessory system (seat heaters, window heaters, multimedia system, screens, ...), so even in short-term trips the 12 battery gets its charge and does not have to provide energy for all accessory. I must say I never had problems with it in 8 years - I changed it after 6 years just to be sure it will never let me down. Did Toyota change anything with the inverter for the next generation (like in the current Prius, the v, ...)? Does anyone here know? The problem for most, non hybrid cars, is that the 12 v battery does not really have a chance to recharge in short-term travel since it also must provide power for our hitec cars with all kinds of "energy-hungry" gadgets. Regards Walter
Nothing changed in this function, eg charging the 12v battery. It only charges when the system is "running" (ready). But all conventional cars do that through their alternator. The big difference is the 12v battery does not have a high current 12v starter. The Prius further protects the 12v battery by keeping 12v receptacles de-energized when the car is off. However it does have lights that can discharge the 12v, such as the hatch bulb.
My question was rather regarding whats happening when the Prius is in READY mode? On the second gen. Prius as soon as the car hits READY the 12 volt battery´s only function is to being charged. It does not provide ANY energy for the 12 volt receptacles. The inverter has a 12 volt output which powers those receptacles. Does anyone know if the new inverter assembly in the current Prius gen. also provides this featured output? This is is rather important when you are doing mostly short-therm trips - let´s say 5 to 10 miles a peace, since 12 v batteries do not favor this behavor! Walter
Its not really a matter of one or the other, both are capable of providing energy as needed. But yes, when the system is in ready mode, the 12v is doing next to nothing. And as has been stated, the 12v batt in a Prius is not negatively impacted by frequent short trips unless you're draining power when the car is off. .
Thanks for the info! On non-hybrid cars the 12 volt battery quickly gets a blow when the vehicle is used mostly in frequent short trips around town with all the goodies on like heated seats, multimedia equipment, rear and front window defroster, etc. ... lots of reports and complaints here in Europe. My Prius gen. 2 which I drove from 2005 to 2013 never let me down regarding this matter. I swapped the 12 v only as a precaution. Knowing that Toyota did not change a thing in the next gen. Prius lets me enjoy my v even more. Walter
Not true. The 12 volt battery always has a load on it especially the headlights and has a pretty good standby load on it too from the SKS system and all the ecu keep alive. That standby load is why the car can't sit for weeks. Many people complain of poor 12 volt life with a car primarily used for short trips which does not enable the Inverter to fully charge the 12 like a decent commute. Nothing has changed from the Gen to Gen concerning the 12 volt. Still needs a decent charge. You will notice this yourself if you do a monthly maintenance charge on the 12 like many people here do or measure the sitting 12 volt battery voltage with a volt meter.
Using the same scangauge II, my Gen 2 was Ready at 13.7 to 13.8 volts, while my v is Ready at 14.3 to 14.4 volts. So that is a change for the better, as the 12 volt battery can charge faster.
I see that on my Gen 2 sometimes also. It all depends on how depleted the charge is on the agm and how healthy the battery is. The charge voltage moves around alot.