Good afternoon, this is our second year doing Electrathon and we are trying to improve our performance and we have a few questions. we heard somewhere that with new batteries we should power cycle them a few times before we race them (discharge to 10v then charge them back up) is this worthwhile and will it improve performance? also, we heard that heating the batteries before charging can improve capacity, is this going to damage the batteries? if it is A good idea, whats the best way to do it (we have a heating pad already) Should we charge the batteries then heat them up, or charge them while they are heating up? Or charge them after they are heated up?
I find that my new lead acid batteries reach peak capacity after about 4 or 5 cycles.
Heating is effective and I get up to a 10 percent increase in capacity at 105F vs 70F. The method I use is to store the batteries charged and then about 10 hours before the race I start heating them using a 300watt waterbed heater (like an oversize heating pad) inside an insulated wooden box. I use a rheostat to control the temperature of the heater. Remember too that just like cooking a turkey, you use a higher temperature in order to get the heat to migrate all the way through the lumps of lead in a timely manner. I tend to run the heater at 120F. The last 2 hours before the race I start charging them again just to top them off once they are up to temperature. Some people will say that heating the batteries shortens their lifespan but the battery under the hood if your car gets hotter than that on a daily basis.
I'm new to Electrathon but, have been doing a lot of research.
I have found that there are a few different variations of Electrathon rules in use (depending on where you want to or plan on racing)
There are the National Electrathon rule book
...& in the Michigan area they go by the Challenge USA rule book
...& in the Wisconsin area they use the NECA (National Electric Car Association) rule book
As far as battery heating, the NECA rules seem to strictly forbid any type of battery heating
Section 8: Battery
Art. 1...All NECA Stock or Open Class batteries
1. Stock and Open Class vehicles may only be powered by 2 Werker WKA12-55P/FR battery, 2
Duracell DURDC12-55C/FR-F 12volt 55Ah AGM, 2 Optima 35 (Red Top), 2 Optima D35
(Yellow Top), or 2 Optima SC25A (Red Top). Batteries will be weighted, inspected, and marked
before the start of each race. (Rule 2, Section, 8, Art. 1)
No heating, alterations, or modifications to the battery are permitted, including modifications
performed by the manufacturer or supplier.
Any batteries approved by OPPD, Electrathon America, or Iowa Electrathon are also legal for
open class only.
* AFAIU Lead Acid batteries should always be kept fully charged (to avoid Sulfication or Sulfer coating of the Lead plates)
...& shouldn't be discharged below ~11V (to avoid internal damage)