Hi,

I have a couple of Yuasa and Power sonic conventional lead-acid bike batteries that I recently purchased for a very good bargain price from a seller. They are new and never used. But unfortunately, the seller did not have the battery acid packs in his possession. So, I have to end up preparing that myself.

I know that I'll need to prepare a 36-38% concentrates Sulfuric acid solution (this is what manufacturers usually use) using my conc. acid is a 95-98% ACS reagent Sulfuric acid. Now I know that they usually use distilled water to prepare them. But I was thinking of it's possible to use Ultrapure De-ionized water instead?

Thanks

@jpanhalt

 

It's up to you. I used to use tap water before I knew better. Now I use distilled water for batteries and radiators.

https://www.uswatersystems.com/deionized-water-vs-distilled-water

 

Yes (http://trontek.com/can-you-use-deionized-water-to-fill-wet-or-flooded-lead-acid-battery/).

Both de-ionization and distillation remove dissolved minerals. Both processes can allow organic (volatile) contaminants to pass through the process. Remember, softened water is not de-ionized water.

 

The water won't stay Deionized for very long just sitting exposed (we have low flow circulation loops on DI water taps to keep it within conductivity specifications) and it sure won't be Deionized after Sulfuric acid is mixed. I use $1 gallons of off-the-shelf grocery store distilled water to top off and water flooded batteries. If you have cheap source of DI water use it but it has to be a DI and ultra-pure source.

 

It's up to you. I used to use tap water before I knew better. Now I use distilled water for batteries and radiators.

https://www.uswatersystems.com/deionized-water-vs-distilled-water

The reason I asked is that I have easier access to a very large quantity of De-ionized water than to distilled water. From the article it looks like DI is fine for battery use.

 

Yes (http://trontek.com/can-you-use-deionized-water-to-fill-wet-or-flooded-lead-acid-battery/).

Both de-ionization and distillation remove dissolved minerals. Both processes can allow organic (volatile) contaminants to pass through the process. Remember, softened water is not de-ionized water.

The DI source I'm using is a laboratory purification system from Milli-Q Direct 16 from Merck. It has a pure section and an Ultrapure. I'll be using the ultrapure section only. The good thing is that the ultrapure section does not have a storage but instead comes live from the system when activated.

 

The water won't stay Deionized for very long just sitting exposed (we have low flow circulation loops on DI water taps to keep it within conductivity specifications) and it sure won't be Deionized after Sulfuric acid is mixed. I use $1 gallons of off-the-shelf grocery store distilled water to top off and water flooded batteries. If you have cheap source of DI water use it but it has to be a DI and ultra-pure source.

Mine is a lab grade ultra-pure source. For me using DI water is cheap as it's abundantly available compared to distilled water. I was just making sure it's safe to use to prepare the acid electrolyte.

 

Your system sounds fine. It's analytical grade water.

The point @nsaspook was making is that such water degrades surprisingly fast when stored. However, what you describe is fresh and is at least as good as anything at the local supermarket. Besides,it is just for batteries, not trace metal analysis.

 

Mine is a lab grade ultra-pure source. For me using DI water is cheap as it's abundantly available compared to DI. I was just making sure it's safe to use to prepare the acid electrolyte.

I have access to literally thousands of gallons of ultra-pure semi-grade DI for free but it's a lot easier to just buy off-the-shelf grocery store distilled water than to lug a multi-gallon liquid chemical container past security after getting a property pass signed by the safety manager. This is extra true during the COVID-19 era.

https://en.wikipedia.org/wiki/Ultrapure_water#UPW_recycling_in_the_semiconductor_industry

Modern Ultrapure Water systems are very effective at removing ionic contamination down to parts per trillion levels (ppt) whereas organic contamination of ultrapure water systems is still in the parts per billion levels (ppb)