# Reenergizing a weak battery **URL:** \ **Category:** Maintenance/Repairs\ **Created:** [January 7, 2009, 1:14am UTC](https://community.cartalk.com/t/reenergizing-a-weak-battery/24514 "2009-01-07T01:14:57Z")\ **Posts on this page:** 12\ **Page:** 1
**Author:** ![sneaky\_pete](https://avatars.discourse-cdn.com/v4/letter/s/f08c70/32.png) [@sneaky\_pete](https://community.cartalk.com/u/sneaky_pete)\ **Post date:** [January 7, 2009, 1:14am UTC](https://community.cartalk.com/t/reenergizing-a-weak-battery/24514/1 "2009-01-07T01:14:57Z")
Many years ago when we (my brothers and me) didn’t have much money, and our car batteries would be getting sluggish, we would remove the electrolyte into an enamel container, flush the battery with sal soda (which I think is calcium carbonate) and replace the electrolyte. I’m wondering if this does anything to extend the life of the battery. I’m well aware of the hazards of handling the electrolyte so that’s not an issue. ---
**Author:** ![ok4450](https://avatars.discourse-cdn.com/v4/letter/o/e9bcb4/32.png) [@ok4450](https://community.cartalk.com/u/ok4450)\ **Post date:** [January 7, 2009, 3:13am UTC](https://community.cartalk.com/t/reenergizing-a-weak-battery/24514/2 "2009-01-07T03:13:21Z")
As far as I’m concerned it is not good for the battery as calcium carbonate or baking soda has a neutralizing effect on battery acid. ---
**Author:** ![JayWB](https://avatars.discourse-cdn.com/v4/letter/j/e480ec/32.png) [@JayWB](https://community.cartalk.com/u/JayWB)\ **Post date:** [January 7, 2009, 3:38am UTC](https://community.cartalk.com/t/reenergizing-a-weak-battery/24514/3 "2009-01-07T03:38:50Z")
I have no idea what the answer to the original question is, but sal soda isn’t the same as baking soda. Sal soda is sodium carbonate. Baking soda is sodium BIcarbonate. Sodium bicarbonate will do a very fine job of completely neutralizing the acid and thus ruining a battery. ---
**Author:** ![ok4450](https://avatars.discourse-cdn.com/v4/letter/o/e9bcb4/32.png) [@ok4450](https://community.cartalk.com/u/ok4450)\ **Post date:** [January 7, 2009, 3:48am UTC](https://community.cartalk.com/t/reenergizing-a-weak-battery/24514/4 "2009-01-07T03:48:10Z")
Sal soda is a type of lime and also a neutralizer. ---
**Author:** ![GreasyJack](https://avatars.discourse-cdn.com/v4/letter/g/df705f/32.png) [@GreasyJack](https://community.cartalk.com/u/GreasyJack)\ **Post date:** [January 7, 2009, 4:38am UTC](https://community.cartalk.com/t/reenergizing-a-weak-battery/24514/5 "2009-01-07T04:38:36Z")
The plug-in battery charger I have has a “desulfate” button on it that will supposedly do the same thing over a period of many hours. I’ve tried it with a couple of weakening batteries I’ve had, but I haven’t had any luck with it. ---
**Author:** ![pleasedodgevan](https://avatars.discourse-cdn.com/v4/letter/p/51bf81/32.png) [@pleasedodgevan](https://community.cartalk.com/u/pleasedodgevan)\ **Post date:** [January 7, 2009, 4:59am UTC](https://community.cartalk.com/t/reenergizing-a-weak-battery/24514/6 "2009-01-07T04:59:13Z")
We don’t hear of that any more because it isn’t really worth the time and effort. Thirty dollars used to be four days pay and if you could save the money you would do it. Now $100 is twelve hours pay at minimum wage. We now go to Wal-Mart and pick up a battery at $40 to $60. Sorry that I can’t answer your question. ---
**Author:** ![ok4450](https://avatars.discourse-cdn.com/v4/letter/o/e9bcb4/32.png) [@ok4450](https://community.cartalk.com/u/ok4450)\ **Post date:** [January 7, 2009, 5:44am UTC](https://community.cartalk.com/t/reenergizing-a-weak-battery/24514/7 "2009-01-07T05:44:40Z")
A “desulphate” button sounds like marketing garbage. Any time a battery is being charged it is being desulphated, no matter if it’s a charger or the alternator on the car, or whatever. That’s interesting; never seen a charger with that phrase on it. The problem is that every second a battery is not being charged it is sulphating. When the charging process starts sulphate is driven off of the lead plates. The process is incremental though. Each time less sulphate is driven off and eventually the battery is weakened beyond hope or flakes off of the plates sink to the bottom of the battery, pile up, short out the plates, and the battery is dead meat at that point. ---
**Author:** ![Manolito](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/manolito/32/3070_2.png) [@Manolito](https://community.cartalk.com/u/Manolito)\ **Post date:** [January 7, 2009, 3:07pm UTC](https://community.cartalk.com/t/reenergizing-a-weak-battery/24514/8 "2009-01-07T15:07:01Z")
Yes, it should clean the plates and extend the life of the battery. It used to be common practice. It would work better if you disposed of the old electrolyte and put in fresh. That is what battery shops did, back in the day when there were such things as battery shops. As pleasedodgevan pointed out, however, in today’s economy, it is not worthwhile, especially now that it costs a fortune to dispose of the used battery acid. However, I suspect that we may see some changes in economic patterns in the next decade or two, and repair rather than replace may come back into style. The skills that us old timers remember may come in very handy. ---
**Author:** ![common-sense-answer](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/common-sense-answer/32/716_2.png) [@common-sense-answer](https://community.cartalk.com/u/common-sense-answer)\ **Post date:** [January 7, 2009, 3:16pm UTC](https://community.cartalk.com/t/reenergizing-a-weak-battery/24514/9 "2009-01-07T15:16:51Z")
Sneaky Pete, Some Current Maintenance-Free Batteries Can’t Be Opened Without Damage. ---
**Author:** ![Whitey](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/whitey/32/24680_2.png) [@Whitey](https://community.cartalk.com/u/Whitey)\ **Post date:** [January 7, 2009, 5:30pm UTC](https://community.cartalk.com/t/reenergizing-a-weak-battery/24514/10 "2009-01-07T17:30:29Z")
I haven’t seen a car battery that cheap in a while. The last time I bought a discount car battery it was $70 or $80. ---
**Author:** ![TwinTurbo](https://avatars.discourse-cdn.com/v4/letter/t/8baadc/32.png) [@TwinTurbo](https://community.cartalk.com/u/TwinTurbo)\ **Post date:** [January 7, 2009, 6:07pm UTC](https://community.cartalk.com/t/reenergizing-a-weak-battery/24514/11 "2009-01-07T18:07:15Z")
You’re right about it sulfating as it discharges and reversing the process upon charging. However, when it is deeply discharged, they turn into sulfate crystals which are much harder to convert back. The process degrades like a death spiral. Normal charging won’t convert them back, you need to apply a higher voltage. To prevent explosion or other damage, they apply this higher voltage in pulses to limit the power. This process takes some time to work properly. Whether or not the budget charger w/a de-sulfate option works properly is another matter. ---
**Author:** ![Beadsandbeads](https://avatars.discourse-cdn.com/v4/letter/b/c57346/32.png) [@Beadsandbeads](https://community.cartalk.com/u/Beadsandbeads)\ **Post date:** [January 7, 2009, 7:27pm UTC](https://community.cartalk.com/t/reenergizing-a-weak-battery/24514/12 "2009-01-07T19:27:44Z")
As Twin and Manolito wrote, the desulphate button is probably not a gimmic. I have seen an auto manufacturer’s TSB outlining the use of their higher-tech charger. They can be used to recover abused batteries.