How ‘bad’ distilled water kill your inverter battery?

I know this is something difficult to believe, but it is true that significant number of lead acid batteries lose their life every year due to addition of bad distilled water that contains high level of total dissolved solids (TDS) which is strictly not recommended for use with lead acid batteries.

What is the recommended Water TDS level for battery use?

Water with 5 ppm TDS or below is recommended for topping up lead acid batteries.

But unfortunately the bottled water you get from roadside shops and petrol stations lacks the TDS level standard recommended for adding with batteries. In our recent research about the quality of the distilled water available in petrol stations and roadside shops shows some shocking results, tds level of bottled distilled water from various petrol bunks exceeds 25 PPM which is unsafe for lead acid batteries.

Due to heavy power outages in most part of our country, use of home ups and inverter batteries has gone up and the demand for distilled water also raised obviously, we have very limited number of companies producing distilled water for chemical labs and lead acid batteries, as usual counterfeit products comes to market without invitation.

Some fraud sellers fill normal municipal water or RO water in used bottles and label them as ‘distilled water’. They have TDS level more than 25 PPM for sure, Buyers should be careful in buying this duplicate distilled water.

Does RO water damage our battery?

I don’t say like that. RO is a different process from distillation. But we have seen many battery service centers use RO water for battery. But they regularly check the TDS level with tds meter to ensure the water tds level is below 5 PPM.

We recommend our readers to use distilled water from reputed battery shops only.

What happens to your inverter battery when you add hard water?

When you top-up your inverter battery with hard water, your battery gradually lose its ability to hold the charge and you will face low back up problem, if you continue to add hard water every time you top up your battery, it will die one day.


hard water

TDS meter

soft water

  • Chandra Sekhar

    Sir, you are doing great job clarifying all doubts regarding inverters and batteries.
    Please provide Facebook sharing option to share info in your site.
    So that more people will be educated very fast.

  • Chandra Sekhar

    sorry sir, I didn’t observe this Facebook sharing option.
    Now I saw this and shared.

    • admin

      Dear chandrasekar,
      Thanks for sharing our page with your facebook friends!

  • cool.raja_2489

    Sir, I want to buy Inverter. i have 3tube lights+3 fans+ samsung LCD tv + normal desk top pc.
    May not be all the lights and fans on at a time when power is off.
    For my requirement which battery and inverter is best.
    Is Luminous Shakti Charge 1000va inverter + Exide IT500 super best ?
    Tell me the best combo.
    Thanks in advance.

    • admin

      Dear Raja,
      850 va pure sinewave inverter with 150 ah battery would be the right choice for your load preference.

      If you face more than 12 hrs power cut per day, then we would recommend Luminous sakti charge with IT 500 super (exide), but we advice not to use LCD TV with Luminous sakti charge inverter. It is a square wave inverter which is good normal fans, tube lights and CFL lamps….not good for sensitive loads.

      But Luminous sakti charge is a Life saver in worst power cut situations.

      If you have power cuts below 10 hrs per day, then we would recommend

      Microtek UPS SEBz850 VA Pure sine wave inverter- Rs.5000/-


      Sukam pure sine wave Model ‘shiny’850va – Rs.5500


      For Battery

      Exide IT500 150 ah Tall tubular battery – Rs.13500 to 14500/- with 48 months warranty

      Exide Mega Inva 150 ah semi tubular battery – Rs.12500/- with 3 years full warranty

      Exide Invertor Plus 150 ah semi tubular battery – Rs.11,100/- with 2 years full warranty

      all the above models are reliable and successful in market, warranty and life expectancy only differs.

  • ktsaravanan05

    Dear Admin,

    Before reading all your posts about “Inverter” and “battery”, i don’t know anything about UPS and Battery.

    But now i got all the necessary details about UPS functions and Battery models.

    Based on your suggestion, i bought EXIDE IT500 and Microtek 850 SEBZ pure sine wave model (which costs Rs.13500 and Rs.5000).

    Now i want to know one thing…

    In this post, you mentioned ‘Bad distilled water kill the battery, so buy branded distilled water with less than 5 ppm’.

    You didn’t mentioned the brand name of that.

    So, Please mention the brand name of the distilled water companies and its price..

    That will also most helpful to me and the readers.


    • admin

      Dear saravanan,
      Thanks for sharing the prices, could you please share your dealers contact details with our readers? it could be useful for other readers from your city.

      We appreciate your idea, we will publish a list of best distilled water brands shortly.

  • Addison Msora

    Hi, I have used rain water, since the beginning of the rainy season. My inverter batteries dont seem to have a problem. I dont have the fancy testers. But all seems well.