you refer to car battery or phone battery?
charging phone only use really small current, your car battery won't deplete so fast.
if scare phone battery die fast, use a reliable car charger, like i using now is Aukey QC2.0.

Yes at least have some protection. For example Aukey.
Safe - With the over-heated, over-current and over-charging protection circuit, our car charger protects your phone and tablet from any harm from the unsteady voltage in the car when charging. So let the charging go itself, just keep your eyes on driving.

Already use for more than 6 months, the Aukey never get hot even during 7-8 hours driving.

The Aukey 5 ports desktop charger, use all 5 ports never get hot. I use cheap 4 ports last time, charge 1 phone already hot.

(one of the sifu here also use aukey - I not going to mention his name)

There is many selection of reputable 12v car charger on lazada/street11

Eg: http://www.lazada.com.my/belkin-dual-usb-c...te-2770725.html

Nope.. i just end user. Sharing a good products. I have Aukey car charger, desktop charger x3, powerbank x2. All come with Quick Charge 2.0 functions. Most latest phone support QC.
I prefer 11street, got so much discounts with coupon. Sometime lazada also give a better price.

Mostly from 11street.my as can use coupon. New member will get a coupon when sign up.
http://www.11street.my/productdetail/qualc...-0-car-16307543

lazada and garage sale in lyn forum also have.

I only test with Sony car charger before, give around 1.2A. I not tested Aukey, my tester doesn't support QC2.0. Wait until I get a new USB tester to test Aukey.

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But I did screenshot Aukey car charger current using Ampere apps before.

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