Parents and caregivers should not assume that every battery-powered product that enters their home is safe for use by children. In many products, for example, the battery is easily accessible or can fall out when the product is dropped. Make sure that the battery compartments of all electronic items are taped shut and loose batteries are always stored out of children's reach.

A button battery stops powering a device way before it runs out of a charge. So, what we think of as a "dead" battery still has the charge to harm a child if it should get caught in their ear, nose and throat or swallowing passage. The higher the voltage of the battery (3V vs. 1.5V) the faster the injury.S

When a child ingest a button battery, their symptoms could be virtually absent or similar to those of a common infection.
-Nasal Cavity or Ear Canal: Drainage or pain may be noted
-Lodged in body: The electric current in a button battery rapidly increases the pH of the tissue adjacent to the battery, causing significant tissue injury even within two hours.  

If a parent or caregiver is suspects their child ingested a button battery, the child needs to be taken immediately to an emergency room.

The diagnosis can be confirmed on a two view x-ray. With an x-ray the determination can be made if it is either a battery or a coin. The button battery has a double ring, or halo sign, as opposed to a single ring of the coin.

The treatment for a button battery stuck within the body is urgent removal in order to minimize local tissue damage. Both immediate assessment of the area of battery contact and follow-up surveillance for long-term., delayed complications should be performed to identify acute or delayed injuries.

REF: https://www.healthychildren.org/English/safety-prevention/at-home/Pages/Button-Battery-Injuries-in-Children-A-Growing-Risk.aspx

Electrical burns or a burn where the skin is charred, leathery, burned away, or has no feeling is severe and should receive medical attention right away. Any blistering, swollen burn that covers an area larger than the size of your child's hand, or a burn that is on the hand, foot, face, genitals, or over a joint is a serious injury and should be seen immediately by a pedestrian or in an emergency room.  If you are worried about a burn, even if it doesn't look like any of the above types of burns, a pedestrian should see it.

Most small, blistering burns can be treated and cared for at home. If you have any questions about whether a burn can be taken care of at home, discuss with your doctor.

1. Cool the burn. Run cool running water over the burn for about five minutes. This helps stop the burning process and decreases pain and swelling. Do not put ice on a burn. Do not rub a burn, because this can worse the injury. Do not break blisters as this can increase the risk of infection at the burn site.

2. Cover the burn. Cover the burned area with a clean bandage that will not stick to the burned site. This helps decrease the risk of infection and decrease pain.

3. Protect the burn. Keep the burn site clean with gentle washing with soap and water. Do not apply any ointments to the burn site unless instruct by your pediatrician. Never apply butter, greases, or other home remedies to a burn before discussing with your pediatrician, as these can increase the risk of infection as well.  

The deeper the burn, the more likely that it will scar. Minor burns that do not blister usually heal without scarring. Burns that form blisters sometimes form a scar or may heal a different color than the surrounding skin.

To minimize scarring, keep burns covered until they have healed with new skin and o not weep any fluid. after this time, it is OK to keep the burn uncovered, but it should be protected from any sun for one year to avoid skin darkening. Sun protection can be coverage with clothing or sunscreen.

According to the World Health Organization, nearly 75% of burns in young children are from liquid, hot tap water, or steam. Another 20% are considered "contact" burns from touching a hot object like a clothes iron or hair appliance.

REF: https://www.healthychildren.org/English/safety-prevention/all-around/Pages/First-Aid-For-Burns.aspx