HV battery Oil pan pre-heating in winter

From Chat GPT


In a gasoline hybrid car, both oil temperature and engine temperature play important roles in fuel consumption, but engine temperature is typically more critical for fuel efficiency. Here's why:

1. Engine Temperature:
   • The engine needs to reach an optimal operating temperature (usually around 190-220°F or 88-104°C) for fuel to burn efficiently. When the engine is cold, it runs less efficiently, consuming more fuel because it uses a richer air-fuel mixture to prevent engine damage.
   • A fully warmed-up engine operates more efficiently, reducing fuel consumption and emissions.
2. Oil Temperature:
   • While oil temperature is also important, it mainly affects engine lubrication and reduces internal friction. If the oil is too cold, it may not flow well, leading to increased friction and wear, which can impact fuel efficiency in the long term.
   • Oil temperature needs to be at a certain level to provide effective lubrication, but it’s generally not as critical as engine temperature for immediate fuel efficiency.

In a hybrid system, the electric motor can assist during colder engine temperatures, which can help reduce the fuel consumption penalty until the engine warms up. However, once the engine reaches its optimal operating temperature, it can deliver maximum fuel efficiency, making engine temperature the more crucial factor for day-to-day fuel consumption.

 

Thank you Mendel and Max 2.

Did the wire insulation melt near the block heater or near the plug? Melting is usually caused by undersized copper wires, copper is very expensive and they try to save on it.

Today I laid down some cardboard boxes on the floor, I removed the underbody cover and measured the depth of the hole, it' s 70mm I couldn't stick a caliper in there to measure the diameter, but I think all block heaters for jap cars use a standardized size, so 18mm, I attached a screenshot of a Mitsubishi forum .


Further I found and ordered standard heating cartridges of same size and rated 380 W 230v, they are sold in pairs, 22 euro including shipping.

https://a.aliexpress.com/_Exuv8OY


The heater is 85mm long, the first 10 mm are just contacts sinked in the ceramic insulation and protected by metal case I'll make a clip with a metal strip and a small hose clamp to fix it to the cylindrical cartridge and click it in to the right position on the engine, similarly to the genuine one, I'll apply some termal compound in between.

I also ordered a few waterproof plugs and sockets for the wiring .

Looking forward to delivery and assembly.

https://a.aliexpress.com/_EIsVRV6

 

ok, I think it wasn't the copper wire thickness the issue here, but the element heat.

If the wires were insulated with fiberglass cloth or silicon instead of standard pvc maybe the short was avoided.

I see DEFA uses a different design where a 10 cm rod between heater and wire dissipates part of the heat and keeps the wires away from each other.


I think the missing heat transfer grease is indeed responsible for making the wire's life even worse.

I'll see if I can find some extra fiberglass sleeves for mine like this