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![Anon](/assets/aa/aa-avatar.png?m=1466990309)
A couple of questions re hybrids -
On a long uphill run such as the Rimutakas, will the battery charge run out and leave the little petrol engine to carry on pulling a heavy car and passengers on its own?
If so would that make for a dangerously sluggish performance?
What is the life expectancy of such batteries and how much do they cost to replace?
Fred
From the "Ask Jack" archives - 14 December 2009
![jbiddle](themes/aaAle/images/interface/profile-pic-placeholder.47cf740a.png)
It depends on the model Hybrid.
For example the Civic only uses the electric motor to boost power on hills etc so in the circumstance you describe I would imagine the battery would not (should not) run completely out of charge.
Remember, it is being charged on a constant basis whenever possible to allow for these types of scenarios. You are correct however, if the battery was to run flat or fail, then the small petrol engine (1.3 litre) would struggle depending on the vehicle load at the time.
The Toyota works the opposite way. It uses its petrol engine (1.5 litre) as the booster so if the battery was to run flat the affect would be less evident in my opinion.
There has been lots of discussion on the battery life of a hybrid but in real life conditions they have stood the test of time remarkably well.
Stories of vehicles travelling over 300,000km's are not unusual. Both Toyota and Honda offer extended warranties on their Hybrid batteries (around ten years I believe) more as a way of portraying confidence in the batteries rather than absorbing huge replacement costs.
The cost of replacement batteries has also reduced in recent times, and is continuing to decrease at regular intervals.