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Weak Battery

Will long term use of a weak battery cause damage to the alternator.

Why ? Are You Thinking Of Installing A Weak Battery ?
By Chance If You’ve Already Got A Weak Battery, Get It Out Of There And Get A New One.


It certainly can.

Yes, an alternator can be damaged trying to charge a worn out battery.

Yes and in the case of my 95 Dodge Dakota a weak/bad battery could damage the ECM and the alternator.

Ed B.

ABSOLUTELY and… copy and paste…see below…

 I have written this description of how important it is to have cleaned and greased battery clamps and terminals sooo many times that I wrote a Word doc and saved it on my laptop just for when I see another question about a weak starter, battery failed alternator etc... or other such issues ALL with a HIGH probability of being caused by corrosion on the battery and its terminals.  When you can visually see corrosion at the battery terminals it is IMPERATIVE that you remove the clamps and use the small battery tool (available for about $3 at all auto parts stores).  When you can see the corrosion it is actually late in the game for cleaning?.make certain it is done BEFORE you can see the corrosion. This little metal tool looks like a bullet?it has an internal and external wire brush designed to help you clean the battery terminals themselves as well as the cars battery clamps?.  Use the tool and clean off the batt terminals and clamps?.Then use grease and liberally apply it to both the batt and clamps.  Put it all back together properly tightened.  ESPECIALLY IN WINTER this corrosion condition will prevent the charge from your alternator from reaching the battery.  The problems that can arise from dirty terminals are MANY?You will think you need a new battery because it seems near dead in the morning or always.  It can run your battery down and actually kill it over the long haul from being in a constant undercharged state.  It can KILL your alternator because it is constantly trying to put charge into a battery ALL THE TIME..i.e. it is working with a high load and all in vain.  The starter of the car will struggle to turn the engine over?.you can also get all sorts of error codes in the car from running it basically in ?Brown-Out? conditions.  The health of the battery terminals and clamps is SO VITALLY IMPORTANT to your vehicle?I cannot overstate this enough.  If you hear that click-click-click in the morning you think your batt died?you get a new batt and the same thing happens all due to corrosion.  Many people get suckered into a new alternator from this?when they don?t need one...yet.  They will soon bec it will burn itself out.  SOOO many batteries have been prematurely replaced because of this simple and often overlooked issue?it is massively common and wreaks havoc on all that suffer from this condition.  It can do surprising things (electrically) to your vehicle?the list is huge.  THIS IS SUPER DUPER IMPORTANT?.PROPERLY CLEAN AND GREASE THOSE BATTERY CONNECTIONS PLEASE!!!  Your car and battery will thank you for it?

Yes. Absolutely. The alternator on your car may be rated at something like 100 amps, meaning it can generate 100 amps of current flow to recharge the battery and supply power to the rest of the electrical accessories. But it can only do that for a short time. A battery that is weak and needs a long time to recharge or is resistant to charge will certainly shorten the life of your alternator.

Think of it this way. You could certainly climb a flight of stairs in 10 seconds. But how long could you keep it up before you have a heart attack?