Battery temp ?

So I'm charging new batteries for my 1/16 summit they are traxxas 7.2 v nimh when they are done the temp is 105 per my ir temp gun is that high

Ok thanks I'm using a venom pro charger for some stupid reason the temp prob reads in c not f so I use my temp gun the packs are 1100 mah the instructions that came with the packs said charge at 1.3 amp I will bring the amps down to 1.1

Very very few chargers sense temperature. To do it, you either need a proprietary battery pack with a built in thermistor or an external temperature probe to attach to the battery. A few of the charger manufactures do offer the temperature probe, but I think I’m the only one I know of that has ever used one. The rise in temperature at full charge is normal (NiCad and NiMh only), but in your case, the rise seems a little excessive. Generally the temperature probes are only used as a protection device (not a charge indicator). Most newer chargers also have a timer for this purpose. Current technology in NiMh chargers does not look for the battery to reach a specific voltage level. There is a characteristic of this battery type that creates a “bump” in the charge voltage at full charge. Almost all chargers now look for that bump. Some do look for excessive voltage as well, but again it’s for a safety shutdown. It’s best not to try to charge these batteries unless they are significantly discharged. Doing that can cause the charger to be fooled since the bump in charge voltage may not be detected (has already happened). So what I’m saying is try not to “top off” your batteries if you can avoid it. If you have to do that, because the batteries have been laying around a while, keep an eye on them and when they start heating up, take them off charge. The best plan is not to charge the batteries until you're about ready to use them. This is especially true of LiPo's since they die an early death if stored fully charged.

My two bits on the topic!
…Tiger

Thanks my charger uses a temp probe that plugs into a USB port on the charger I've been setting the battery on the probe all though I've been thinking about stealing a oven MIT from the kitchen just have to wait for the wife to look the other way lol

It's really difficult to get good thermal conductivity between an external probe and the battery. I don't know what your stuff looks like so it's hard to know what to suggest. Maybe tape the probe to the battery and then put it on the mit or better yet a piece of styrofoam with a little indentation in it for the probe. You don't want to have the probe on anything that sucks the heat back out of it or even have good enough air flow to cool it. Most chargers i've seen have the temperature trip point programmable. You might look at that. The other possibility is that the probe is out of calibration. If the charger allows you to read the temperature, you can check the calibration with warm water of a know temperature.

...Tiger

Here is a chart that might help you understand better what I was saying above. It show the voltage bump that the charger detects and how that relates to temperature rise. You can see on the chart that the temp is about 45C when the bump ends and the charger shuts down. This assumes that the probe is really seeing the temperature of the cell. If it's not, then the actually cell temp could be higher. However, if the charger is working properly, the high temp shouldn't happen, because the end of the bump should have shut the charger down.
...Tiger

Thanks guys the graphs help me to visualize what you was saying